PROJECT REPORT

ON Proxy Server (IN LINUX)

INDEX

LINUX OPERATING SYSTEM

History of Linux

UNIX

In order to understand the popularity of Linux

we need to travel back in time about 30 years

agoImagine computers as big as houses even

stadiums While the sizes of those

computers posed substantial problems there

was one thing that made this even worse every

computer had a different operating

systemSoftware was always customized to serve a specific purpose and

software for one given system didnt run on another system Being able to

work with one system didnt automatically mean that you could work with

another It was difficult both for the users and the system

administratorsComputers were extremely expensive then and sacrifices

had to be made even after the original purchase just to get the users to

understand how they worked The total cost per unit of computing power

was enormousTechnologically the world was not quite that advanced so

they had to live with the size for another decade In1969 a team of

developers in the Bell Labs laboratories started working on a solution for

the softwareproblem to address these compatibility issues They

developed a new operating system which was

1 Simple and elegant

2 Written in the C programming language instead of in assembly code

3 Able to recycle code

The Bell Labs developers named their project UNIX The code recycling

features were very important Until then all commercially available

computer systems were written in a code specifically developed for one

system UNIX on the other hand needed only a small piece of that special

code which is now commonly named the kernel This kernel is the only

piece of code that needs to be adapted for every specific system and forms

the base of the UNIX system The operating system and all other functions

were built around this kernel and written in a higher programming

language C

Introduction to Linux

This language was especially developed for

creating the UNIX system Using this new

technique it was much easier to develop an

operating system that could run on many

different types of hardware The software

vendors were quick to adapt since they could sell

ten times more software almost effortlessly Weird new situations came in

existence imagine for instance computers from different vendors

communicating in the same network or users working on different systems

without the need for extra education to use another computer UNIX did a

great deal to help users become compatible with different systems

Throughout the next couple of decades the development of UNIX

continued More things became possible to do and more hardware and

software vendors added support for UNIX to their products UNIX was

initially found only in very large environments with mainframes and

minicomputers (note that a PC is a micro computer) You had to work at a

university for the government or for large financial corporations in order to

get your hands on a UNIX system

But smaller computers were being developed and by the end of the 80s

many people had home computers By that time there were several

versions of UNIX available for the PC architecture but none of them were

truly free and more important they were all terribly slow so most people

ran MS DOS or Windows 31 on their home PCs

Linus and Linux

By the beginning of the 90s home PCs were finally powerful enough to run

a full blown UNIX Linus Torvalds a young man studying computer science

at the university of Helsinki thought it would be a good idea to have some

sort of freely available academic version of UNIX and promptly started to

code it was Linus goal to have a free system that was completely

compliant with the original UNIX That is why he asked for POSIX standards

POSIX still being the standard for UNIX In those days plug-and-play wasnt

invented yet but so many people were interested in having a UNIX system

of their own that this was only a small obstacle New drivers became

available for all kinds of new hardware at a continuously rising speed

Almost as soon as a new piece of hardware became available someone

bought it and submitted it to the Linux test as the system was gradually

being called releasing more free code for an

ever wider range of hardware These coders didnt stop at their PCs every

piece of hardware they could find was useful for Linux Back then those

people were called nerds or freaks but it didnt matter to them as long

as the supported hardware list grew longer and longer Thanks to these

people Linux is now not only ideal to run on new PCs but is also the

system of choice for old and exotic hardware that would be useless if Linux

didnt existTwo years after Linus post there were 12000 Linux users The

project popular with hobbyists grew steadily all the while staying within

the bounds of the POSIX standard All the features of UNIX were added over

the next couple of years resulting in the mature operating system Linux

has become today Linux is a full UNIX clone fit for use on workstations as

well as on middle-range and high-end servers Today a lot of the important

players on the hard- and software market each have their team of Linux

developers at your local dealers you can even buy pre-installed Linux

systems with official support ndash even though there is still a lot of hard- and

software that is not supported too

Current application of Linux systems

Today Linux has joined the desktop market Linux developers concentrated on networking and

services in the beginning and office applications have been the last barrier to be taken down

We dont like to admit that Microsoft is ruling this market so plenty of alternatives have been

started over the last couple of years to make Linux an acceptable choice as a workstation

providing an easy user interface and MS compatible office applications like word processors

spreadsheets presentations and the like On the server side Linux is well-known as a stable

and reliable platform providing database and trading services for companies like Amazon the

well-known online bookshop US Post Office the German army and many others Especially

Internet providers and Internet service providers have grown fond of Linux as firewall proxy-

and web server and you will find a Linux box within reach of every UNIX system

administrator who appreciates a comfortable management station Clusters of Linux machines

are used in the

creation of movies such as Titanic Shrek and others In post offices they are the nerve

centers that route mail and in large search engine clusters are used to perform internet

searchesThese are only a few of the thousands of heavy-duty jobs that Linux is performing

day-to-day across the world It is also worth to note that modern Linux not only runs on

workstations mid- and high-end servers but also on gadgets like PDAs mobiles a shipload

of embedded applications and even on experimental wristwatches This makes Linux the only

operating system in the world covering such a wide range of hardware

Is Linux difficult or not

Whether Linux is difficult to learn depends on the person

youre asking Experienced UNIX users will say no because

Linux is an ideal operating system for power-users and

programmers because it has been and is being developed by

such people Everything a good programmer can wish for is

available compilers libraries development and debugging

tools These packages come with every standard Linux

distribution The C-compiler is included for free ndash as opposed

to many UNIX distributions demanding licensing fees for this tool All the documentation and

manuals are there and examples are often included to help you get started in no time It feels

like UNIX and switching between UNIX and Linux is a natural thing In the early days of

Linux being an expert was kind of required to start using the system Those who mastered

Linux felt better than the rest of the lusers who hadnt seen the light yet It was common

practice to tell a beginning user to RTFM (read the manuals) While the manuals were on

every system it was difficult to find the documentation and even if someone did explanations

were in such technical terms that the new user became easily discouraged from learning the

system The Linux-using community started to realize that if Linux was ever to be an important

player on the operating system market there had to be some serious changes in the

accessibility of the system

Linux for non-experienced users

Companies such as RedHat SuSE and Mandriva have sprung up providing packaged Linux

distributions suitable for mass consumption They integrated a great deal of graphical user

interfaces (GUIs) developed by the community in order to ease management of programs and

services As a Linux user today you have all the means of getting to know your system inside

out but it is no longer necessary to have that knowledge in order to make the system comply to

your requests

Now a days you can log in graphically and start all required applications without even having

to type a single character while you still have the ability to access the core of the system if

needed Because of its structure Linux allows a user to grow into the system it equally fits

new and experienced users New users are not forced to do difficult things while experienced

users are not forced to work in the same way they did when they first started learning Linux

While development in the service area continues great things are being done for desktop users

generally considered as the group least likely to know how a system works Developers of

desktop applications are making incredible efforts to make the most beautiful desktops youve

ever seen or to make your Linux machine look just like your former MS Windows or an Apple

workstation The latest developments also include 3D acceleration support and support for

USB devices single-click updates of system and packages and so on Linux has these and

tries to present all available services in a logical form that ordinary people can understand

Structures of UNIX LINUX

The highlighting features of this operating system are

(i) Portable ndash Written in C language

(ii) Source code is available in high level language(C )

(iii) Multi-user system implements Time-sharing

(iv) Powerful-defines the concept of power as not the programs but the interaction of programs

The structure of UNIX is as follows

Most prominent are

1 Red Hat LINUX ndash Educational and commercial

2 Caldera LINUX ndash Business oriented

3 SUSE LINUX ndash Retailers and applications

4 Turbo LINUX ndash Multilanguage

5 Debian LINUX ndash Truly free no commercial version

6 Slackware LINUX ndash Most UNIX like

Kernel Version

First official version was 002 and first stable version was 10 As per changes kernel goes

through a

(i) Development phase where lot of changes and modifications are being added and

developed It is denoted by odd number in the versions eg 11 21 etc

(ii) Stabilization phase where small modifications are made to the kernel It is denoted by even

numbers in the versions eg 12 22 Current stable kernel is 2210

Hence Linux architecture as simplified can be seen as-

A seed like core or the kernel which performs rapid switching between tasks under execution

attaches drivers to the few hardware processes inter-process communication prevents

interference with one-another and protects itself from corrupt program routines This kernel

while running grows into a fully Blown OS Linux shell to provide a powerful user interface

while still protecting itself from user-mode unauthorized access It provides the user an

environment to work upon and take ownership of it by customizing it

FEATURErsquoS OF LINUX

MULTI-TASKING In Linux it is possible to have many programs running at

the same time which means that not only can you have many programs going at

once but that the Linux operating system can self have programs running in the

background (and this is the main reason why Linux is used as server)So that

back-ground processes can run side by side These processes are called

DIEMANS

MULTI-USER Not only can you have many user accounts available on a

Linux system you can also have multiple logged in and working on the system

at the same time Users can have their own environment arranged in the way

they want and there own desktop interfaces with icons menus and

applications User accounts can be password protected

GRAPHICAL USER INTERFACE The framework for working with

graphical application in Linux is known as X-windows system or simply X

The X based desktop environment provides the look and feel of GUI Icons

menus themes etc

HARDWARE SUPPORT Linux can configure support for almost every kind

of hardware that can be connected to a computer

NETWORKING CONNECTIVITY To connect a Linux system to a network

Linux offer support for a variety of local area network bolts modems and

serial devices

NETWORK SERVER Linux is the best for providing networking services to

the client computer on RAM or the entire

internet Therefore Linux can be used to act

a print server file server mail server

web server etc

Installing Red Hat Enterprise Linux 5

This appendix is straightforward It illustrates the steps required to install Red Hat Enterprise

Linux 5 Server on your computer using graphical and text based installation methods Both are

governed by the Red Hat program known as Anaconda

Graphical Installation

To install Red Hat Enterprise Linux 5 on your computer take the following steps

1 Select and insert the media that yoursquoll use to boot the Red Hat Enterprise Linux 5

installation program It can be the first Red Hat Enterprise Linux 5 CD a boot CD

created from the bootiso file from the images directory of the first installation CD or a

boot USB key created from the diskbootimg file from the same directory

2 Power on your system Press the appropriate key typically ESC F12 or DEL to access the

boot menu shown here If a boot menu isnrsquot available yoursquoll need to adjust the boot sequence

in the computer BIOS which you can then use to boot directly from your selected media Set

your computerrsquos BIOS to boot from the first installation CD or USB drive Details vary by PC

Make sure your BIOS saves your changes before you reboot

3 Type linux askmethod when you see the boot

4 Choose a language and select OK

5 Select a keyboard and select OK

6 Set up an NFS installation method and select OK

7 Start configuring your network as shown If you have a DHCP server on your network that

is simplestmdashunless of course yoursquore told to enable static addressing during your exam For

this installation disable DHCP for both IPv4 and IPv6addressing If you donrsquot have an IPv6-

capable DHCP server or router disable IPv6 addressing completely Select OK If you enable

DHCP skip the next step

8 Add static address information for your network Use the IP Address Gateway and Name

Server (DNS) addresses associated with your existing network Select OK

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

INDEX

LINUX OPERATING SYSTEM

History of Linux

UNIX

In order to understand the popularity of Linux

we need to travel back in time about 30 years

agoImagine computers as big as houses even

stadiums While the sizes of those

computers posed substantial problems there

was one thing that made this even worse every

computer had a different operating

systemSoftware was always customized to serve a specific purpose and

software for one given system didnt run on another system Being able to

work with one system didnt automatically mean that you could work with

another It was difficult both for the users and the system

administratorsComputers were extremely expensive then and sacrifices

had to be made even after the original purchase just to get the users to

understand how they worked The total cost per unit of computing power

was enormousTechnologically the world was not quite that advanced so

they had to live with the size for another decade In1969 a team of

developers in the Bell Labs laboratories started working on a solution for

the softwareproblem to address these compatibility issues They

developed a new operating system which was

1 Simple and elegant

2 Written in the C programming language instead of in assembly code

3 Able to recycle code

The Bell Labs developers named their project UNIX The code recycling

features were very important Until then all commercially available

computer systems were written in a code specifically developed for one

system UNIX on the other hand needed only a small piece of that special

code which is now commonly named the kernel This kernel is the only

piece of code that needs to be adapted for every specific system and forms

the base of the UNIX system The operating system and all other functions

were built around this kernel and written in a higher programming

language C

Introduction to Linux

This language was especially developed for

creating the UNIX system Using this new

technique it was much easier to develop an

operating system that could run on many

different types of hardware The software

vendors were quick to adapt since they could sell

ten times more software almost effortlessly Weird new situations came in

existence imagine for instance computers from different vendors

communicating in the same network or users working on different systems

without the need for extra education to use another computer UNIX did a

great deal to help users become compatible with different systems

Throughout the next couple of decades the development of UNIX

continued More things became possible to do and more hardware and

software vendors added support for UNIX to their products UNIX was

initially found only in very large environments with mainframes and

minicomputers (note that a PC is a micro computer) You had to work at a

university for the government or for large financial corporations in order to

get your hands on a UNIX system

But smaller computers were being developed and by the end of the 80s

many people had home computers By that time there were several

versions of UNIX available for the PC architecture but none of them were

truly free and more important they were all terribly slow so most people

ran MS DOS or Windows 31 on their home PCs

Linus and Linux

By the beginning of the 90s home PCs were finally powerful enough to run

a full blown UNIX Linus Torvalds a young man studying computer science

at the university of Helsinki thought it would be a good idea to have some

sort of freely available academic version of UNIX and promptly started to

code it was Linus goal to have a free system that was completely

compliant with the original UNIX That is why he asked for POSIX standards

POSIX still being the standard for UNIX In those days plug-and-play wasnt

invented yet but so many people were interested in having a UNIX system

of their own that this was only a small obstacle New drivers became

available for all kinds of new hardware at a continuously rising speed

Almost as soon as a new piece of hardware became available someone

bought it and submitted it to the Linux test as the system was gradually

being called releasing more free code for an

ever wider range of hardware These coders didnt stop at their PCs every

piece of hardware they could find was useful for Linux Back then those

people were called nerds or freaks but it didnt matter to them as long

as the supported hardware list grew longer and longer Thanks to these

people Linux is now not only ideal to run on new PCs but is also the

system of choice for old and exotic hardware that would be useless if Linux

didnt existTwo years after Linus post there were 12000 Linux users The

project popular with hobbyists grew steadily all the while staying within

the bounds of the POSIX standard All the features of UNIX were added over

the next couple of years resulting in the mature operating system Linux

has become today Linux is a full UNIX clone fit for use on workstations as

well as on middle-range and high-end servers Today a lot of the important

players on the hard- and software market each have their team of Linux

developers at your local dealers you can even buy pre-installed Linux

systems with official support ndash even though there is still a lot of hard- and

software that is not supported too

Current application of Linux systems

Today Linux has joined the desktop market Linux developers concentrated on networking and

services in the beginning and office applications have been the last barrier to be taken down

We dont like to admit that Microsoft is ruling this market so plenty of alternatives have been

started over the last couple of years to make Linux an acceptable choice as a workstation

providing an easy user interface and MS compatible office applications like word processors

spreadsheets presentations and the like On the server side Linux is well-known as a stable

and reliable platform providing database and trading services for companies like Amazon the

well-known online bookshop US Post Office the German army and many others Especially

Internet providers and Internet service providers have grown fond of Linux as firewall proxy-

and web server and you will find a Linux box within reach of every UNIX system

administrator who appreciates a comfortable management station Clusters of Linux machines

are used in the

creation of movies such as Titanic Shrek and others In post offices they are the nerve

centers that route mail and in large search engine clusters are used to perform internet

searchesThese are only a few of the thousands of heavy-duty jobs that Linux is performing

day-to-day across the world It is also worth to note that modern Linux not only runs on

workstations mid- and high-end servers but also on gadgets like PDAs mobiles a shipload

of embedded applications and even on experimental wristwatches This makes Linux the only

operating system in the world covering such a wide range of hardware

Is Linux difficult or not

Whether Linux is difficult to learn depends on the person

youre asking Experienced UNIX users will say no because

Linux is an ideal operating system for power-users and

programmers because it has been and is being developed by

such people Everything a good programmer can wish for is

available compilers libraries development and debugging

tools These packages come with every standard Linux

distribution The C-compiler is included for free ndash as opposed

to many UNIX distributions demanding licensing fees for this tool All the documentation and

manuals are there and examples are often included to help you get started in no time It feels

like UNIX and switching between UNIX and Linux is a natural thing In the early days of

Linux being an expert was kind of required to start using the system Those who mastered

Linux felt better than the rest of the lusers who hadnt seen the light yet It was common

practice to tell a beginning user to RTFM (read the manuals) While the manuals were on

every system it was difficult to find the documentation and even if someone did explanations

were in such technical terms that the new user became easily discouraged from learning the

system The Linux-using community started to realize that if Linux was ever to be an important

player on the operating system market there had to be some serious changes in the

accessibility of the system

Linux for non-experienced users

Companies such as RedHat SuSE and Mandriva have sprung up providing packaged Linux

distributions suitable for mass consumption They integrated a great deal of graphical user

interfaces (GUIs) developed by the community in order to ease management of programs and

services As a Linux user today you have all the means of getting to know your system inside

out but it is no longer necessary to have that knowledge in order to make the system comply to

your requests

Now a days you can log in graphically and start all required applications without even having

to type a single character while you still have the ability to access the core of the system if

needed Because of its structure Linux allows a user to grow into the system it equally fits

new and experienced users New users are not forced to do difficult things while experienced

users are not forced to work in the same way they did when they first started learning Linux

While development in the service area continues great things are being done for desktop users

generally considered as the group least likely to know how a system works Developers of

desktop applications are making incredible efforts to make the most beautiful desktops youve

ever seen or to make your Linux machine look just like your former MS Windows or an Apple

workstation The latest developments also include 3D acceleration support and support for

USB devices single-click updates of system and packages and so on Linux has these and

tries to present all available services in a logical form that ordinary people can understand

Structures of UNIX LINUX

The highlighting features of this operating system are

(i) Portable ndash Written in C language

(ii) Source code is available in high level language(C )

(iii) Multi-user system implements Time-sharing

(iv) Powerful-defines the concept of power as not the programs but the interaction of programs

The structure of UNIX is as follows

Most prominent are

1 Red Hat LINUX ndash Educational and commercial

2 Caldera LINUX ndash Business oriented

3 SUSE LINUX ndash Retailers and applications

4 Turbo LINUX ndash Multilanguage

5 Debian LINUX ndash Truly free no commercial version

6 Slackware LINUX ndash Most UNIX like

Kernel Version

First official version was 002 and first stable version was 10 As per changes kernel goes

through a

(i) Development phase where lot of changes and modifications are being added and

developed It is denoted by odd number in the versions eg 11 21 etc

(ii) Stabilization phase where small modifications are made to the kernel It is denoted by even

numbers in the versions eg 12 22 Current stable kernel is 2210

Hence Linux architecture as simplified can be seen as-

A seed like core or the kernel which performs rapid switching between tasks under execution

attaches drivers to the few hardware processes inter-process communication prevents

interference with one-another and protects itself from corrupt program routines This kernel

while running grows into a fully Blown OS Linux shell to provide a powerful user interface

while still protecting itself from user-mode unauthorized access It provides the user an

environment to work upon and take ownership of it by customizing it

FEATURErsquoS OF LINUX

MULTI-TASKING In Linux it is possible to have many programs running at

the same time which means that not only can you have many programs going at

once but that the Linux operating system can self have programs running in the

background (and this is the main reason why Linux is used as server)So that

back-ground processes can run side by side These processes are called

DIEMANS

MULTI-USER Not only can you have many user accounts available on a

Linux system you can also have multiple logged in and working on the system

at the same time Users can have their own environment arranged in the way

they want and there own desktop interfaces with icons menus and

applications User accounts can be password protected

GRAPHICAL USER INTERFACE The framework for working with

graphical application in Linux is known as X-windows system or simply X

The X based desktop environment provides the look and feel of GUI Icons

menus themes etc

HARDWARE SUPPORT Linux can configure support for almost every kind

of hardware that can be connected to a computer

NETWORKING CONNECTIVITY To connect a Linux system to a network

Linux offer support for a variety of local area network bolts modems and

serial devices

NETWORK SERVER Linux is the best for providing networking services to

the client computer on RAM or the entire

internet Therefore Linux can be used to act

a print server file server mail server

web server etc

Installing Red Hat Enterprise Linux 5

This appendix is straightforward It illustrates the steps required to install Red Hat Enterprise

Linux 5 Server on your computer using graphical and text based installation methods Both are

governed by the Red Hat program known as Anaconda

Graphical Installation

To install Red Hat Enterprise Linux 5 on your computer take the following steps

1 Select and insert the media that yoursquoll use to boot the Red Hat Enterprise Linux 5

installation program It can be the first Red Hat Enterprise Linux 5 CD a boot CD

created from the bootiso file from the images directory of the first installation CD or a

boot USB key created from the diskbootimg file from the same directory

2 Power on your system Press the appropriate key typically ESC F12 or DEL to access the

boot menu shown here If a boot menu isnrsquot available yoursquoll need to adjust the boot sequence

in the computer BIOS which you can then use to boot directly from your selected media Set

your computerrsquos BIOS to boot from the first installation CD or USB drive Details vary by PC

Make sure your BIOS saves your changes before you reboot

3 Type linux askmethod when you see the boot

4 Choose a language and select OK

5 Select a keyboard and select OK

6 Set up an NFS installation method and select OK

7 Start configuring your network as shown If you have a DHCP server on your network that

is simplestmdashunless of course yoursquore told to enable static addressing during your exam For

this installation disable DHCP for both IPv4 and IPv6addressing If you donrsquot have an IPv6-

capable DHCP server or router disable IPv6 addressing completely Select OK If you enable

DHCP skip the next step

8 Add static address information for your network Use the IP Address Gateway and Name

Server (DNS) addresses associated with your existing network Select OK

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

LINUX OPERATING SYSTEM

History of Linux

UNIX

In order to understand the popularity of Linux

we need to travel back in time about 30 years

agoImagine computers as big as houses even

stadiums While the sizes of those

computers posed substantial problems there

was one thing that made this even worse every

computer had a different operating

systemSoftware was always customized to serve a specific purpose and

software for one given system didnt run on another system Being able to

work with one system didnt automatically mean that you could work with

another It was difficult both for the users and the system

administratorsComputers were extremely expensive then and sacrifices

had to be made even after the original purchase just to get the users to

understand how they worked The total cost per unit of computing power

was enormousTechnologically the world was not quite that advanced so

they had to live with the size for another decade In1969 a team of

developers in the Bell Labs laboratories started working on a solution for

the softwareproblem to address these compatibility issues They

developed a new operating system which was

1 Simple and elegant

2 Written in the C programming language instead of in assembly code

3 Able to recycle code

The Bell Labs developers named their project UNIX The code recycling

features were very important Until then all commercially available

computer systems were written in a code specifically developed for one

system UNIX on the other hand needed only a small piece of that special

code which is now commonly named the kernel This kernel is the only

piece of code that needs to be adapted for every specific system and forms

the base of the UNIX system The operating system and all other functions

were built around this kernel and written in a higher programming

language C

Introduction to Linux

This language was especially developed for

creating the UNIX system Using this new

technique it was much easier to develop an

operating system that could run on many

different types of hardware The software

vendors were quick to adapt since they could sell

ten times more software almost effortlessly Weird new situations came in

existence imagine for instance computers from different vendors

communicating in the same network or users working on different systems

without the need for extra education to use another computer UNIX did a

great deal to help users become compatible with different systems

Throughout the next couple of decades the development of UNIX

continued More things became possible to do and more hardware and

software vendors added support for UNIX to their products UNIX was

initially found only in very large environments with mainframes and

minicomputers (note that a PC is a micro computer) You had to work at a

university for the government or for large financial corporations in order to

get your hands on a UNIX system

But smaller computers were being developed and by the end of the 80s

many people had home computers By that time there were several

versions of UNIX available for the PC architecture but none of them were

truly free and more important they were all terribly slow so most people

ran MS DOS or Windows 31 on their home PCs

Linus and Linux

By the beginning of the 90s home PCs were finally powerful enough to run

a full blown UNIX Linus Torvalds a young man studying computer science

at the university of Helsinki thought it would be a good idea to have some

sort of freely available academic version of UNIX and promptly started to

code it was Linus goal to have a free system that was completely

compliant with the original UNIX That is why he asked for POSIX standards

POSIX still being the standard for UNIX In those days plug-and-play wasnt

invented yet but so many people were interested in having a UNIX system

of their own that this was only a small obstacle New drivers became

available for all kinds of new hardware at a continuously rising speed

Almost as soon as a new piece of hardware became available someone

bought it and submitted it to the Linux test as the system was gradually

being called releasing more free code for an

ever wider range of hardware These coders didnt stop at their PCs every

piece of hardware they could find was useful for Linux Back then those

people were called nerds or freaks but it didnt matter to them as long

as the supported hardware list grew longer and longer Thanks to these

people Linux is now not only ideal to run on new PCs but is also the

system of choice for old and exotic hardware that would be useless if Linux

didnt existTwo years after Linus post there were 12000 Linux users The

project popular with hobbyists grew steadily all the while staying within

the bounds of the POSIX standard All the features of UNIX were added over

the next couple of years resulting in the mature operating system Linux

has become today Linux is a full UNIX clone fit for use on workstations as

well as on middle-range and high-end servers Today a lot of the important

players on the hard- and software market each have their team of Linux

developers at your local dealers you can even buy pre-installed Linux

systems with official support ndash even though there is still a lot of hard- and

software that is not supported too

Current application of Linux systems

Today Linux has joined the desktop market Linux developers concentrated on networking and

services in the beginning and office applications have been the last barrier to be taken down

We dont like to admit that Microsoft is ruling this market so plenty of alternatives have been

started over the last couple of years to make Linux an acceptable choice as a workstation

providing an easy user interface and MS compatible office applications like word processors

spreadsheets presentations and the like On the server side Linux is well-known as a stable

and reliable platform providing database and trading services for companies like Amazon the

well-known online bookshop US Post Office the German army and many others Especially

Internet providers and Internet service providers have grown fond of Linux as firewall proxy-

and web server and you will find a Linux box within reach of every UNIX system

administrator who appreciates a comfortable management station Clusters of Linux machines

are used in the

creation of movies such as Titanic Shrek and others In post offices they are the nerve

centers that route mail and in large search engine clusters are used to perform internet

searchesThese are only a few of the thousands of heavy-duty jobs that Linux is performing

day-to-day across the world It is also worth to note that modern Linux not only runs on

workstations mid- and high-end servers but also on gadgets like PDAs mobiles a shipload

of embedded applications and even on experimental wristwatches This makes Linux the only

operating system in the world covering such a wide range of hardware

Is Linux difficult or not

Whether Linux is difficult to learn depends on the person

youre asking Experienced UNIX users will say no because

Linux is an ideal operating system for power-users and

programmers because it has been and is being developed by

such people Everything a good programmer can wish for is

available compilers libraries development and debugging

tools These packages come with every standard Linux

distribution The C-compiler is included for free ndash as opposed

to many UNIX distributions demanding licensing fees for this tool All the documentation and

manuals are there and examples are often included to help you get started in no time It feels

like UNIX and switching between UNIX and Linux is a natural thing In the early days of

Linux being an expert was kind of required to start using the system Those who mastered

Linux felt better than the rest of the lusers who hadnt seen the light yet It was common

practice to tell a beginning user to RTFM (read the manuals) While the manuals were on

every system it was difficult to find the documentation and even if someone did explanations

were in such technical terms that the new user became easily discouraged from learning the

system The Linux-using community started to realize that if Linux was ever to be an important

player on the operating system market there had to be some serious changes in the

accessibility of the system

Linux for non-experienced users

Companies such as RedHat SuSE and Mandriva have sprung up providing packaged Linux

distributions suitable for mass consumption They integrated a great deal of graphical user

interfaces (GUIs) developed by the community in order to ease management of programs and

services As a Linux user today you have all the means of getting to know your system inside

out but it is no longer necessary to have that knowledge in order to make the system comply to

your requests

Now a days you can log in graphically and start all required applications without even having

to type a single character while you still have the ability to access the core of the system if

needed Because of its structure Linux allows a user to grow into the system it equally fits

new and experienced users New users are not forced to do difficult things while experienced

users are not forced to work in the same way they did when they first started learning Linux

While development in the service area continues great things are being done for desktop users

generally considered as the group least likely to know how a system works Developers of

desktop applications are making incredible efforts to make the most beautiful desktops youve

ever seen or to make your Linux machine look just like your former MS Windows or an Apple

workstation The latest developments also include 3D acceleration support and support for

USB devices single-click updates of system and packages and so on Linux has these and

tries to present all available services in a logical form that ordinary people can understand

Structures of UNIX LINUX

The highlighting features of this operating system are

(i) Portable ndash Written in C language

(ii) Source code is available in high level language(C )

(iii) Multi-user system implements Time-sharing

(iv) Powerful-defines the concept of power as not the programs but the interaction of programs

The structure of UNIX is as follows

Most prominent are

1 Red Hat LINUX ndash Educational and commercial

2 Caldera LINUX ndash Business oriented

3 SUSE LINUX ndash Retailers and applications

4 Turbo LINUX ndash Multilanguage

5 Debian LINUX ndash Truly free no commercial version

6 Slackware LINUX ndash Most UNIX like

Kernel Version

First official version was 002 and first stable version was 10 As per changes kernel goes

through a

(i) Development phase where lot of changes and modifications are being added and

developed It is denoted by odd number in the versions eg 11 21 etc

(ii) Stabilization phase where small modifications are made to the kernel It is denoted by even

numbers in the versions eg 12 22 Current stable kernel is 2210

Hence Linux architecture as simplified can be seen as-

A seed like core or the kernel which performs rapid switching between tasks under execution

attaches drivers to the few hardware processes inter-process communication prevents

interference with one-another and protects itself from corrupt program routines This kernel

while running grows into a fully Blown OS Linux shell to provide a powerful user interface

while still protecting itself from user-mode unauthorized access It provides the user an

environment to work upon and take ownership of it by customizing it

FEATURErsquoS OF LINUX

MULTI-TASKING In Linux it is possible to have many programs running at

the same time which means that not only can you have many programs going at

once but that the Linux operating system can self have programs running in the

background (and this is the main reason why Linux is used as server)So that

back-ground processes can run side by side These processes are called

DIEMANS

MULTI-USER Not only can you have many user accounts available on a

Linux system you can also have multiple logged in and working on the system

at the same time Users can have their own environment arranged in the way

they want and there own desktop interfaces with icons menus and

applications User accounts can be password protected

GRAPHICAL USER INTERFACE The framework for working with

graphical application in Linux is known as X-windows system or simply X

The X based desktop environment provides the look and feel of GUI Icons

menus themes etc

HARDWARE SUPPORT Linux can configure support for almost every kind

of hardware that can be connected to a computer

NETWORKING CONNECTIVITY To connect a Linux system to a network

Linux offer support for a variety of local area network bolts modems and

serial devices

NETWORK SERVER Linux is the best for providing networking services to

the client computer on RAM or the entire

internet Therefore Linux can be used to act

a print server file server mail server

web server etc

Installing Red Hat Enterprise Linux 5

This appendix is straightforward It illustrates the steps required to install Red Hat Enterprise

Linux 5 Server on your computer using graphical and text based installation methods Both are

governed by the Red Hat program known as Anaconda

Graphical Installation

To install Red Hat Enterprise Linux 5 on your computer take the following steps

1 Select and insert the media that yoursquoll use to boot the Red Hat Enterprise Linux 5

installation program It can be the first Red Hat Enterprise Linux 5 CD a boot CD

created from the bootiso file from the images directory of the first installation CD or a

boot USB key created from the diskbootimg file from the same directory

2 Power on your system Press the appropriate key typically ESC F12 or DEL to access the

boot menu shown here If a boot menu isnrsquot available yoursquoll need to adjust the boot sequence

in the computer BIOS which you can then use to boot directly from your selected media Set

your computerrsquos BIOS to boot from the first installation CD or USB drive Details vary by PC

Make sure your BIOS saves your changes before you reboot

3 Type linux askmethod when you see the boot

4 Choose a language and select OK

5 Select a keyboard and select OK

6 Set up an NFS installation method and select OK

7 Start configuring your network as shown If you have a DHCP server on your network that

is simplestmdashunless of course yoursquore told to enable static addressing during your exam For

this installation disable DHCP for both IPv4 and IPv6addressing If you donrsquot have an IPv6-

capable DHCP server or router disable IPv6 addressing completely Select OK If you enable

DHCP skip the next step

8 Add static address information for your network Use the IP Address Gateway and Name

Server (DNS) addresses associated with your existing network Select OK

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

administratorsComputers were extremely expensive then and sacrifices

had to be made even after the original purchase just to get the users to

understand how they worked The total cost per unit of computing power

was enormousTechnologically the world was not quite that advanced so

they had to live with the size for another decade In1969 a team of

developers in the Bell Labs laboratories started working on a solution for

the softwareproblem to address these compatibility issues They

developed a new operating system which was

1 Simple and elegant

2 Written in the C programming language instead of in assembly code

3 Able to recycle code

The Bell Labs developers named their project UNIX The code recycling

features were very important Until then all commercially available

computer systems were written in a code specifically developed for one

system UNIX on the other hand needed only a small piece of that special

code which is now commonly named the kernel This kernel is the only

piece of code that needs to be adapted for every specific system and forms

the base of the UNIX system The operating system and all other functions

were built around this kernel and written in a higher programming

language C

Introduction to Linux

This language was especially developed for

creating the UNIX system Using this new

technique it was much easier to develop an

operating system that could run on many

different types of hardware The software

vendors were quick to adapt since they could sell

ten times more software almost effortlessly Weird new situations came in

existence imagine for instance computers from different vendors

communicating in the same network or users working on different systems

without the need for extra education to use another computer UNIX did a

great deal to help users become compatible with different systems

Throughout the next couple of decades the development of UNIX

continued More things became possible to do and more hardware and

software vendors added support for UNIX to their products UNIX was

initially found only in very large environments with mainframes and

minicomputers (note that a PC is a micro computer) You had to work at a

university for the government or for large financial corporations in order to

get your hands on a UNIX system

But smaller computers were being developed and by the end of the 80s

many people had home computers By that time there were several

versions of UNIX available for the PC architecture but none of them were

truly free and more important they were all terribly slow so most people

ran MS DOS or Windows 31 on their home PCs

Linus and Linux

By the beginning of the 90s home PCs were finally powerful enough to run

a full blown UNIX Linus Torvalds a young man studying computer science

at the university of Helsinki thought it would be a good idea to have some

sort of freely available academic version of UNIX and promptly started to

code it was Linus goal to have a free system that was completely

compliant with the original UNIX That is why he asked for POSIX standards

POSIX still being the standard for UNIX In those days plug-and-play wasnt

invented yet but so many people were interested in having a UNIX system

of their own that this was only a small obstacle New drivers became

available for all kinds of new hardware at a continuously rising speed

Almost as soon as a new piece of hardware became available someone

bought it and submitted it to the Linux test as the system was gradually

being called releasing more free code for an

ever wider range of hardware These coders didnt stop at their PCs every

piece of hardware they could find was useful for Linux Back then those

people were called nerds or freaks but it didnt matter to them as long

as the supported hardware list grew longer and longer Thanks to these

people Linux is now not only ideal to run on new PCs but is also the

system of choice for old and exotic hardware that would be useless if Linux

didnt existTwo years after Linus post there were 12000 Linux users The

project popular with hobbyists grew steadily all the while staying within

the bounds of the POSIX standard All the features of UNIX were added over

the next couple of years resulting in the mature operating system Linux

has become today Linux is a full UNIX clone fit for use on workstations as

well as on middle-range and high-end servers Today a lot of the important

players on the hard- and software market each have their team of Linux

developers at your local dealers you can even buy pre-installed Linux

systems with official support ndash even though there is still a lot of hard- and

software that is not supported too

Current application of Linux systems

Today Linux has joined the desktop market Linux developers concentrated on networking and

services in the beginning and office applications have been the last barrier to be taken down

We dont like to admit that Microsoft is ruling this market so plenty of alternatives have been

started over the last couple of years to make Linux an acceptable choice as a workstation

providing an easy user interface and MS compatible office applications like word processors

spreadsheets presentations and the like On the server side Linux is well-known as a stable

and reliable platform providing database and trading services for companies like Amazon the

well-known online bookshop US Post Office the German army and many others Especially

Internet providers and Internet service providers have grown fond of Linux as firewall proxy-

and web server and you will find a Linux box within reach of every UNIX system

administrator who appreciates a comfortable management station Clusters of Linux machines

are used in the

creation of movies such as Titanic Shrek and others In post offices they are the nerve

centers that route mail and in large search engine clusters are used to perform internet

searchesThese are only a few of the thousands of heavy-duty jobs that Linux is performing

day-to-day across the world It is also worth to note that modern Linux not only runs on

workstations mid- and high-end servers but also on gadgets like PDAs mobiles a shipload

of embedded applications and even on experimental wristwatches This makes Linux the only

operating system in the world covering such a wide range of hardware

Is Linux difficult or not

Whether Linux is difficult to learn depends on the person

youre asking Experienced UNIX users will say no because

Linux is an ideal operating system for power-users and

programmers because it has been and is being developed by

such people Everything a good programmer can wish for is

available compilers libraries development and debugging

tools These packages come with every standard Linux

distribution The C-compiler is included for free ndash as opposed

to many UNIX distributions demanding licensing fees for this tool All the documentation and

manuals are there and examples are often included to help you get started in no time It feels

like UNIX and switching between UNIX and Linux is a natural thing In the early days of

Linux being an expert was kind of required to start using the system Those who mastered

Linux felt better than the rest of the lusers who hadnt seen the light yet It was common

practice to tell a beginning user to RTFM (read the manuals) While the manuals were on

every system it was difficult to find the documentation and even if someone did explanations

were in such technical terms that the new user became easily discouraged from learning the

system The Linux-using community started to realize that if Linux was ever to be an important

player on the operating system market there had to be some serious changes in the

accessibility of the system

Linux for non-experienced users

Companies such as RedHat SuSE and Mandriva have sprung up providing packaged Linux

distributions suitable for mass consumption They integrated a great deal of graphical user

interfaces (GUIs) developed by the community in order to ease management of programs and

services As a Linux user today you have all the means of getting to know your system inside

out but it is no longer necessary to have that knowledge in order to make the system comply to

your requests

Now a days you can log in graphically and start all required applications without even having

to type a single character while you still have the ability to access the core of the system if

needed Because of its structure Linux allows a user to grow into the system it equally fits

new and experienced users New users are not forced to do difficult things while experienced

users are not forced to work in the same way they did when they first started learning Linux

While development in the service area continues great things are being done for desktop users

generally considered as the group least likely to know how a system works Developers of

desktop applications are making incredible efforts to make the most beautiful desktops youve

ever seen or to make your Linux machine look just like your former MS Windows or an Apple

workstation The latest developments also include 3D acceleration support and support for

USB devices single-click updates of system and packages and so on Linux has these and

tries to present all available services in a logical form that ordinary people can understand

Structures of UNIX LINUX

The highlighting features of this operating system are

(i) Portable ndash Written in C language

(ii) Source code is available in high level language(C )

(iii) Multi-user system implements Time-sharing

(iv) Powerful-defines the concept of power as not the programs but the interaction of programs

The structure of UNIX is as follows

Most prominent are

1 Red Hat LINUX ndash Educational and commercial

2 Caldera LINUX ndash Business oriented

3 SUSE LINUX ndash Retailers and applications

4 Turbo LINUX ndash Multilanguage

5 Debian LINUX ndash Truly free no commercial version

6 Slackware LINUX ndash Most UNIX like

Kernel Version

First official version was 002 and first stable version was 10 As per changes kernel goes

through a

(i) Development phase where lot of changes and modifications are being added and

developed It is denoted by odd number in the versions eg 11 21 etc

(ii) Stabilization phase where small modifications are made to the kernel It is denoted by even

numbers in the versions eg 12 22 Current stable kernel is 2210

Hence Linux architecture as simplified can be seen as-

A seed like core or the kernel which performs rapid switching between tasks under execution

attaches drivers to the few hardware processes inter-process communication prevents

interference with one-another and protects itself from corrupt program routines This kernel

while running grows into a fully Blown OS Linux shell to provide a powerful user interface

while still protecting itself from user-mode unauthorized access It provides the user an

environment to work upon and take ownership of it by customizing it

FEATURErsquoS OF LINUX

MULTI-TASKING In Linux it is possible to have many programs running at

the same time which means that not only can you have many programs going at

once but that the Linux operating system can self have programs running in the

background (and this is the main reason why Linux is used as server)So that

back-ground processes can run side by side These processes are called

DIEMANS

MULTI-USER Not only can you have many user accounts available on a

Linux system you can also have multiple logged in and working on the system

at the same time Users can have their own environment arranged in the way

they want and there own desktop interfaces with icons menus and

applications User accounts can be password protected

GRAPHICAL USER INTERFACE The framework for working with

graphical application in Linux is known as X-windows system or simply X

The X based desktop environment provides the look and feel of GUI Icons

menus themes etc

HARDWARE SUPPORT Linux can configure support for almost every kind

of hardware that can be connected to a computer

NETWORKING CONNECTIVITY To connect a Linux system to a network

Linux offer support for a variety of local area network bolts modems and

serial devices

NETWORK SERVER Linux is the best for providing networking services to

the client computer on RAM or the entire

internet Therefore Linux can be used to act

a print server file server mail server

web server etc

Installing Red Hat Enterprise Linux 5

This appendix is straightforward It illustrates the steps required to install Red Hat Enterprise

Linux 5 Server on your computer using graphical and text based installation methods Both are

governed by the Red Hat program known as Anaconda

Graphical Installation

To install Red Hat Enterprise Linux 5 on your computer take the following steps

1 Select and insert the media that yoursquoll use to boot the Red Hat Enterprise Linux 5

installation program It can be the first Red Hat Enterprise Linux 5 CD a boot CD

created from the bootiso file from the images directory of the first installation CD or a

boot USB key created from the diskbootimg file from the same directory

2 Power on your system Press the appropriate key typically ESC F12 or DEL to access the

boot menu shown here If a boot menu isnrsquot available yoursquoll need to adjust the boot sequence

in the computer BIOS which you can then use to boot directly from your selected media Set

your computerrsquos BIOS to boot from the first installation CD or USB drive Details vary by PC

Make sure your BIOS saves your changes before you reboot

3 Type linux askmethod when you see the boot

4 Choose a language and select OK

5 Select a keyboard and select OK

6 Set up an NFS installation method and select OK

7 Start configuring your network as shown If you have a DHCP server on your network that

is simplestmdashunless of course yoursquore told to enable static addressing during your exam For

this installation disable DHCP for both IPv4 and IPv6addressing If you donrsquot have an IPv6-

capable DHCP server or router disable IPv6 addressing completely Select OK If you enable

DHCP skip the next step

8 Add static address information for your network Use the IP Address Gateway and Name

Server (DNS) addresses associated with your existing network Select OK

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

ten times more software almost effortlessly Weird new situations came in

existence imagine for instance computers from different vendors

communicating in the same network or users working on different systems

without the need for extra education to use another computer UNIX did a

great deal to help users become compatible with different systems

Throughout the next couple of decades the development of UNIX

continued More things became possible to do and more hardware and

software vendors added support for UNIX to their products UNIX was

initially found only in very large environments with mainframes and

minicomputers (note that a PC is a micro computer) You had to work at a

university for the government or for large financial corporations in order to

get your hands on a UNIX system

But smaller computers were being developed and by the end of the 80s

many people had home computers By that time there were several

versions of UNIX available for the PC architecture but none of them were

truly free and more important they were all terribly slow so most people

ran MS DOS or Windows 31 on their home PCs

Linus and Linux

By the beginning of the 90s home PCs were finally powerful enough to run

a full blown UNIX Linus Torvalds a young man studying computer science

at the university of Helsinki thought it would be a good idea to have some

sort of freely available academic version of UNIX and promptly started to

code it was Linus goal to have a free system that was completely

compliant with the original UNIX That is why he asked for POSIX standards

POSIX still being the standard for UNIX In those days plug-and-play wasnt

invented yet but so many people were interested in having a UNIX system

of their own that this was only a small obstacle New drivers became

available for all kinds of new hardware at a continuously rising speed

Almost as soon as a new piece of hardware became available someone

bought it and submitted it to the Linux test as the system was gradually

being called releasing more free code for an

ever wider range of hardware These coders didnt stop at their PCs every

piece of hardware they could find was useful for Linux Back then those

people were called nerds or freaks but it didnt matter to them as long

as the supported hardware list grew longer and longer Thanks to these

people Linux is now not only ideal to run on new PCs but is also the

system of choice for old and exotic hardware that would be useless if Linux

didnt existTwo years after Linus post there were 12000 Linux users The

project popular with hobbyists grew steadily all the while staying within

the bounds of the POSIX standard All the features of UNIX were added over

the next couple of years resulting in the mature operating system Linux

has become today Linux is a full UNIX clone fit for use on workstations as

well as on middle-range and high-end servers Today a lot of the important

players on the hard- and software market each have their team of Linux

developers at your local dealers you can even buy pre-installed Linux

systems with official support ndash even though there is still a lot of hard- and

software that is not supported too

Current application of Linux systems

Today Linux has joined the desktop market Linux developers concentrated on networking and

services in the beginning and office applications have been the last barrier to be taken down

We dont like to admit that Microsoft is ruling this market so plenty of alternatives have been

started over the last couple of years to make Linux an acceptable choice as a workstation

providing an easy user interface and MS compatible office applications like word processors

spreadsheets presentations and the like On the server side Linux is well-known as a stable

and reliable platform providing database and trading services for companies like Amazon the

well-known online bookshop US Post Office the German army and many others Especially

Internet providers and Internet service providers have grown fond of Linux as firewall proxy-

and web server and you will find a Linux box within reach of every UNIX system

administrator who appreciates a comfortable management station Clusters of Linux machines

are used in the

creation of movies such as Titanic Shrek and others In post offices they are the nerve

centers that route mail and in large search engine clusters are used to perform internet

searchesThese are only a few of the thousands of heavy-duty jobs that Linux is performing

day-to-day across the world It is also worth to note that modern Linux not only runs on

workstations mid- and high-end servers but also on gadgets like PDAs mobiles a shipload

of embedded applications and even on experimental wristwatches This makes Linux the only

operating system in the world covering such a wide range of hardware

Is Linux difficult or not

Whether Linux is difficult to learn depends on the person

youre asking Experienced UNIX users will say no because

Linux is an ideal operating system for power-users and

programmers because it has been and is being developed by

such people Everything a good programmer can wish for is

available compilers libraries development and debugging

tools These packages come with every standard Linux

distribution The C-compiler is included for free ndash as opposed

to many UNIX distributions demanding licensing fees for this tool All the documentation and

manuals are there and examples are often included to help you get started in no time It feels

like UNIX and switching between UNIX and Linux is a natural thing In the early days of

Linux being an expert was kind of required to start using the system Those who mastered

Linux felt better than the rest of the lusers who hadnt seen the light yet It was common

practice to tell a beginning user to RTFM (read the manuals) While the manuals were on

every system it was difficult to find the documentation and even if someone did explanations

were in such technical terms that the new user became easily discouraged from learning the

system The Linux-using community started to realize that if Linux was ever to be an important

player on the operating system market there had to be some serious changes in the

accessibility of the system

Linux for non-experienced users

Companies such as RedHat SuSE and Mandriva have sprung up providing packaged Linux

distributions suitable for mass consumption They integrated a great deal of graphical user

interfaces (GUIs) developed by the community in order to ease management of programs and

services As a Linux user today you have all the means of getting to know your system inside

out but it is no longer necessary to have that knowledge in order to make the system comply to

your requests

Now a days you can log in graphically and start all required applications without even having

to type a single character while you still have the ability to access the core of the system if

needed Because of its structure Linux allows a user to grow into the system it equally fits

new and experienced users New users are not forced to do difficult things while experienced

users are not forced to work in the same way they did when they first started learning Linux

While development in the service area continues great things are being done for desktop users

generally considered as the group least likely to know how a system works Developers of

desktop applications are making incredible efforts to make the most beautiful desktops youve

ever seen or to make your Linux machine look just like your former MS Windows or an Apple

workstation The latest developments also include 3D acceleration support and support for

USB devices single-click updates of system and packages and so on Linux has these and

tries to present all available services in a logical form that ordinary people can understand

Structures of UNIX LINUX

The highlighting features of this operating system are

(i) Portable ndash Written in C language

(ii) Source code is available in high level language(C )

(iii) Multi-user system implements Time-sharing

(iv) Powerful-defines the concept of power as not the programs but the interaction of programs

The structure of UNIX is as follows

Most prominent are

1 Red Hat LINUX ndash Educational and commercial

2 Caldera LINUX ndash Business oriented

3 SUSE LINUX ndash Retailers and applications

4 Turbo LINUX ndash Multilanguage

5 Debian LINUX ndash Truly free no commercial version

6 Slackware LINUX ndash Most UNIX like

Kernel Version

First official version was 002 and first stable version was 10 As per changes kernel goes

through a

(i) Development phase where lot of changes and modifications are being added and

developed It is denoted by odd number in the versions eg 11 21 etc

(ii) Stabilization phase where small modifications are made to the kernel It is denoted by even

numbers in the versions eg 12 22 Current stable kernel is 2210

Hence Linux architecture as simplified can be seen as-

A seed like core or the kernel which performs rapid switching between tasks under execution

attaches drivers to the few hardware processes inter-process communication prevents

interference with one-another and protects itself from corrupt program routines This kernel

while running grows into a fully Blown OS Linux shell to provide a powerful user interface

while still protecting itself from user-mode unauthorized access It provides the user an

environment to work upon and take ownership of it by customizing it

FEATURErsquoS OF LINUX

MULTI-TASKING In Linux it is possible to have many programs running at

the same time which means that not only can you have many programs going at

once but that the Linux operating system can self have programs running in the

background (and this is the main reason why Linux is used as server)So that

back-ground processes can run side by side These processes are called

DIEMANS

MULTI-USER Not only can you have many user accounts available on a

Linux system you can also have multiple logged in and working on the system

at the same time Users can have their own environment arranged in the way

they want and there own desktop interfaces with icons menus and

applications User accounts can be password protected

GRAPHICAL USER INTERFACE The framework for working with

graphical application in Linux is known as X-windows system or simply X

The X based desktop environment provides the look and feel of GUI Icons

menus themes etc

HARDWARE SUPPORT Linux can configure support for almost every kind

of hardware that can be connected to a computer

NETWORKING CONNECTIVITY To connect a Linux system to a network

Linux offer support for a variety of local area network bolts modems and

serial devices

NETWORK SERVER Linux is the best for providing networking services to

the client computer on RAM or the entire

internet Therefore Linux can be used to act

a print server file server mail server

web server etc

Installing Red Hat Enterprise Linux 5

This appendix is straightforward It illustrates the steps required to install Red Hat Enterprise

Linux 5 Server on your computer using graphical and text based installation methods Both are

governed by the Red Hat program known as Anaconda

Graphical Installation

To install Red Hat Enterprise Linux 5 on your computer take the following steps

1 Select and insert the media that yoursquoll use to boot the Red Hat Enterprise Linux 5

installation program It can be the first Red Hat Enterprise Linux 5 CD a boot CD

created from the bootiso file from the images directory of the first installation CD or a

boot USB key created from the diskbootimg file from the same directory

2 Power on your system Press the appropriate key typically ESC F12 or DEL to access the

boot menu shown here If a boot menu isnrsquot available yoursquoll need to adjust the boot sequence

in the computer BIOS which you can then use to boot directly from your selected media Set

your computerrsquos BIOS to boot from the first installation CD or USB drive Details vary by PC

Make sure your BIOS saves your changes before you reboot

3 Type linux askmethod when you see the boot

4 Choose a language and select OK

5 Select a keyboard and select OK

6 Set up an NFS installation method and select OK

7 Start configuring your network as shown If you have a DHCP server on your network that

is simplestmdashunless of course yoursquore told to enable static addressing during your exam For

this installation disable DHCP for both IPv4 and IPv6addressing If you donrsquot have an IPv6-

capable DHCP server or router disable IPv6 addressing completely Select OK If you enable

DHCP skip the next step

8 Add static address information for your network Use the IP Address Gateway and Name

Server (DNS) addresses associated with your existing network Select OK

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

By the beginning of the 90s home PCs were finally powerful enough to run

a full blown UNIX Linus Torvalds a young man studying computer science

at the university of Helsinki thought it would be a good idea to have some

sort of freely available academic version of UNIX and promptly started to

code it was Linus goal to have a free system that was completely

compliant with the original UNIX That is why he asked for POSIX standards

POSIX still being the standard for UNIX In those days plug-and-play wasnt

invented yet but so many people were interested in having a UNIX system

of their own that this was only a small obstacle New drivers became

available for all kinds of new hardware at a continuously rising speed

Almost as soon as a new piece of hardware became available someone

bought it and submitted it to the Linux test as the system was gradually

being called releasing more free code for an

ever wider range of hardware These coders didnt stop at their PCs every

piece of hardware they could find was useful for Linux Back then those

people were called nerds or freaks but it didnt matter to them as long

as the supported hardware list grew longer and longer Thanks to these

people Linux is now not only ideal to run on new PCs but is also the

system of choice for old and exotic hardware that would be useless if Linux

didnt existTwo years after Linus post there were 12000 Linux users The

project popular with hobbyists grew steadily all the while staying within

the bounds of the POSIX standard All the features of UNIX were added over

the next couple of years resulting in the mature operating system Linux

has become today Linux is a full UNIX clone fit for use on workstations as

well as on middle-range and high-end servers Today a lot of the important

players on the hard- and software market each have their team of Linux

developers at your local dealers you can even buy pre-installed Linux

systems with official support ndash even though there is still a lot of hard- and

software that is not supported too

Current application of Linux systems

Today Linux has joined the desktop market Linux developers concentrated on networking and

services in the beginning and office applications have been the last barrier to be taken down

We dont like to admit that Microsoft is ruling this market so plenty of alternatives have been

started over the last couple of years to make Linux an acceptable choice as a workstation

providing an easy user interface and MS compatible office applications like word processors

spreadsheets presentations and the like On the server side Linux is well-known as a stable

and reliable platform providing database and trading services for companies like Amazon the

well-known online bookshop US Post Office the German army and many others Especially

Internet providers and Internet service providers have grown fond of Linux as firewall proxy-

and web server and you will find a Linux box within reach of every UNIX system

administrator who appreciates a comfortable management station Clusters of Linux machines

are used in the

creation of movies such as Titanic Shrek and others In post offices they are the nerve

centers that route mail and in large search engine clusters are used to perform internet

searchesThese are only a few of the thousands of heavy-duty jobs that Linux is performing

day-to-day across the world It is also worth to note that modern Linux not only runs on

workstations mid- and high-end servers but also on gadgets like PDAs mobiles a shipload

of embedded applications and even on experimental wristwatches This makes Linux the only

operating system in the world covering such a wide range of hardware

Is Linux difficult or not

Whether Linux is difficult to learn depends on the person

youre asking Experienced UNIX users will say no because

Linux is an ideal operating system for power-users and

programmers because it has been and is being developed by

such people Everything a good programmer can wish for is

available compilers libraries development and debugging

tools These packages come with every standard Linux

distribution The C-compiler is included for free ndash as opposed

to many UNIX distributions demanding licensing fees for this tool All the documentation and

manuals are there and examples are often included to help you get started in no time It feels

like UNIX and switching between UNIX and Linux is a natural thing In the early days of

Linux being an expert was kind of required to start using the system Those who mastered

Linux felt better than the rest of the lusers who hadnt seen the light yet It was common

practice to tell a beginning user to RTFM (read the manuals) While the manuals were on

every system it was difficult to find the documentation and even if someone did explanations

were in such technical terms that the new user became easily discouraged from learning the

system The Linux-using community started to realize that if Linux was ever to be an important

player on the operating system market there had to be some serious changes in the

accessibility of the system

Linux for non-experienced users

Companies such as RedHat SuSE and Mandriva have sprung up providing packaged Linux

distributions suitable for mass consumption They integrated a great deal of graphical user

interfaces (GUIs) developed by the community in order to ease management of programs and

services As a Linux user today you have all the means of getting to know your system inside

out but it is no longer necessary to have that knowledge in order to make the system comply to

your requests

Now a days you can log in graphically and start all required applications without even having

to type a single character while you still have the ability to access the core of the system if

needed Because of its structure Linux allows a user to grow into the system it equally fits

new and experienced users New users are not forced to do difficult things while experienced

users are not forced to work in the same way they did when they first started learning Linux

While development in the service area continues great things are being done for desktop users

generally considered as the group least likely to know how a system works Developers of

desktop applications are making incredible efforts to make the most beautiful desktops youve

ever seen or to make your Linux machine look just like your former MS Windows or an Apple

workstation The latest developments also include 3D acceleration support and support for

USB devices single-click updates of system and packages and so on Linux has these and

tries to present all available services in a logical form that ordinary people can understand

Structures of UNIX LINUX

The highlighting features of this operating system are

(i) Portable ndash Written in C language

(ii) Source code is available in high level language(C )

(iii) Multi-user system implements Time-sharing

(iv) Powerful-defines the concept of power as not the programs but the interaction of programs

The structure of UNIX is as follows

Most prominent are

1 Red Hat LINUX ndash Educational and commercial

2 Caldera LINUX ndash Business oriented

3 SUSE LINUX ndash Retailers and applications

4 Turbo LINUX ndash Multilanguage

5 Debian LINUX ndash Truly free no commercial version

6 Slackware LINUX ndash Most UNIX like

Kernel Version

First official version was 002 and first stable version was 10 As per changes kernel goes

through a

(i) Development phase where lot of changes and modifications are being added and

developed It is denoted by odd number in the versions eg 11 21 etc

(ii) Stabilization phase where small modifications are made to the kernel It is denoted by even

numbers in the versions eg 12 22 Current stable kernel is 2210

Hence Linux architecture as simplified can be seen as-

A seed like core or the kernel which performs rapid switching between tasks under execution

attaches drivers to the few hardware processes inter-process communication prevents

interference with one-another and protects itself from corrupt program routines This kernel

while running grows into a fully Blown OS Linux shell to provide a powerful user interface

while still protecting itself from user-mode unauthorized access It provides the user an

environment to work upon and take ownership of it by customizing it

FEATURErsquoS OF LINUX

MULTI-TASKING In Linux it is possible to have many programs running at

the same time which means that not only can you have many programs going at

once but that the Linux operating system can self have programs running in the

background (and this is the main reason why Linux is used as server)So that

back-ground processes can run side by side These processes are called

DIEMANS

MULTI-USER Not only can you have many user accounts available on a

Linux system you can also have multiple logged in and working on the system

at the same time Users can have their own environment arranged in the way

they want and there own desktop interfaces with icons menus and

applications User accounts can be password protected

GRAPHICAL USER INTERFACE The framework for working with

graphical application in Linux is known as X-windows system or simply X

The X based desktop environment provides the look and feel of GUI Icons

menus themes etc

HARDWARE SUPPORT Linux can configure support for almost every kind

of hardware that can be connected to a computer

NETWORKING CONNECTIVITY To connect a Linux system to a network

Linux offer support for a variety of local area network bolts modems and

serial devices

NETWORK SERVER Linux is the best for providing networking services to

the client computer on RAM or the entire

internet Therefore Linux can be used to act

a print server file server mail server

web server etc

Installing Red Hat Enterprise Linux 5

This appendix is straightforward It illustrates the steps required to install Red Hat Enterprise

Linux 5 Server on your computer using graphical and text based installation methods Both are

governed by the Red Hat program known as Anaconda

Graphical Installation

To install Red Hat Enterprise Linux 5 on your computer take the following steps

1 Select and insert the media that yoursquoll use to boot the Red Hat Enterprise Linux 5

installation program It can be the first Red Hat Enterprise Linux 5 CD a boot CD

created from the bootiso file from the images directory of the first installation CD or a

boot USB key created from the diskbootimg file from the same directory

2 Power on your system Press the appropriate key typically ESC F12 or DEL to access the

boot menu shown here If a boot menu isnrsquot available yoursquoll need to adjust the boot sequence

in the computer BIOS which you can then use to boot directly from your selected media Set

your computerrsquos BIOS to boot from the first installation CD or USB drive Details vary by PC

Make sure your BIOS saves your changes before you reboot

3 Type linux askmethod when you see the boot

4 Choose a language and select OK

5 Select a keyboard and select OK

6 Set up an NFS installation method and select OK

7 Start configuring your network as shown If you have a DHCP server on your network that

is simplestmdashunless of course yoursquore told to enable static addressing during your exam For

this installation disable DHCP for both IPv4 and IPv6addressing If you donrsquot have an IPv6-

capable DHCP server or router disable IPv6 addressing completely Select OK If you enable

DHCP skip the next step

8 Add static address information for your network Use the IP Address Gateway and Name

Server (DNS) addresses associated with your existing network Select OK

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

Current application of Linux systems

Today Linux has joined the desktop market Linux developers concentrated on networking and

services in the beginning and office applications have been the last barrier to be taken down

We dont like to admit that Microsoft is ruling this market so plenty of alternatives have been

started over the last couple of years to make Linux an acceptable choice as a workstation

providing an easy user interface and MS compatible office applications like word processors

spreadsheets presentations and the like On the server side Linux is well-known as a stable

and reliable platform providing database and trading services for companies like Amazon the

well-known online bookshop US Post Office the German army and many others Especially

Internet providers and Internet service providers have grown fond of Linux as firewall proxy-

and web server and you will find a Linux box within reach of every UNIX system

administrator who appreciates a comfortable management station Clusters of Linux machines

are used in the

creation of movies such as Titanic Shrek and others In post offices they are the nerve

centers that route mail and in large search engine clusters are used to perform internet

searchesThese are only a few of the thousands of heavy-duty jobs that Linux is performing

day-to-day across the world It is also worth to note that modern Linux not only runs on

workstations mid- and high-end servers but also on gadgets like PDAs mobiles a shipload

of embedded applications and even on experimental wristwatches This makes Linux the only

operating system in the world covering such a wide range of hardware

Is Linux difficult or not

Whether Linux is difficult to learn depends on the person

youre asking Experienced UNIX users will say no because

Linux is an ideal operating system for power-users and

programmers because it has been and is being developed by

such people Everything a good programmer can wish for is

available compilers libraries development and debugging

tools These packages come with every standard Linux

distribution The C-compiler is included for free ndash as opposed

to many UNIX distributions demanding licensing fees for this tool All the documentation and

manuals are there and examples are often included to help you get started in no time It feels

like UNIX and switching between UNIX and Linux is a natural thing In the early days of

Linux being an expert was kind of required to start using the system Those who mastered

Linux felt better than the rest of the lusers who hadnt seen the light yet It was common

practice to tell a beginning user to RTFM (read the manuals) While the manuals were on

every system it was difficult to find the documentation and even if someone did explanations

were in such technical terms that the new user became easily discouraged from learning the

system The Linux-using community started to realize that if Linux was ever to be an important

player on the operating system market there had to be some serious changes in the

accessibility of the system

Linux for non-experienced users

Companies such as RedHat SuSE and Mandriva have sprung up providing packaged Linux

distributions suitable for mass consumption They integrated a great deal of graphical user

interfaces (GUIs) developed by the community in order to ease management of programs and

services As a Linux user today you have all the means of getting to know your system inside

out but it is no longer necessary to have that knowledge in order to make the system comply to

your requests

Now a days you can log in graphically and start all required applications without even having

to type a single character while you still have the ability to access the core of the system if

needed Because of its structure Linux allows a user to grow into the system it equally fits

new and experienced users New users are not forced to do difficult things while experienced

users are not forced to work in the same way they did when they first started learning Linux

While development in the service area continues great things are being done for desktop users

generally considered as the group least likely to know how a system works Developers of

desktop applications are making incredible efforts to make the most beautiful desktops youve

ever seen or to make your Linux machine look just like your former MS Windows or an Apple

workstation The latest developments also include 3D acceleration support and support for

USB devices single-click updates of system and packages and so on Linux has these and

tries to present all available services in a logical form that ordinary people can understand

Structures of UNIX LINUX

The highlighting features of this operating system are

(i) Portable ndash Written in C language

(ii) Source code is available in high level language(C )

(iii) Multi-user system implements Time-sharing

(iv) Powerful-defines the concept of power as not the programs but the interaction of programs

The structure of UNIX is as follows

Most prominent are

1 Red Hat LINUX ndash Educational and commercial

2 Caldera LINUX ndash Business oriented

3 SUSE LINUX ndash Retailers and applications

4 Turbo LINUX ndash Multilanguage

5 Debian LINUX ndash Truly free no commercial version

6 Slackware LINUX ndash Most UNIX like

Kernel Version

First official version was 002 and first stable version was 10 As per changes kernel goes

through a

(i) Development phase where lot of changes and modifications are being added and

developed It is denoted by odd number in the versions eg 11 21 etc

(ii) Stabilization phase where small modifications are made to the kernel It is denoted by even

numbers in the versions eg 12 22 Current stable kernel is 2210

Hence Linux architecture as simplified can be seen as-

A seed like core or the kernel which performs rapid switching between tasks under execution

attaches drivers to the few hardware processes inter-process communication prevents

interference with one-another and protects itself from corrupt program routines This kernel

while running grows into a fully Blown OS Linux shell to provide a powerful user interface

while still protecting itself from user-mode unauthorized access It provides the user an

environment to work upon and take ownership of it by customizing it

FEATURErsquoS OF LINUX

MULTI-TASKING In Linux it is possible to have many programs running at

the same time which means that not only can you have many programs going at

once but that the Linux operating system can self have programs running in the

background (and this is the main reason why Linux is used as server)So that

back-ground processes can run side by side These processes are called

DIEMANS

MULTI-USER Not only can you have many user accounts available on a

Linux system you can also have multiple logged in and working on the system

at the same time Users can have their own environment arranged in the way

they want and there own desktop interfaces with icons menus and

applications User accounts can be password protected

GRAPHICAL USER INTERFACE The framework for working with

graphical application in Linux is known as X-windows system or simply X

The X based desktop environment provides the look and feel of GUI Icons

menus themes etc

HARDWARE SUPPORT Linux can configure support for almost every kind

of hardware that can be connected to a computer

NETWORKING CONNECTIVITY To connect a Linux system to a network

Linux offer support for a variety of local area network bolts modems and

serial devices

NETWORK SERVER Linux is the best for providing networking services to

the client computer on RAM or the entire

internet Therefore Linux can be used to act

a print server file server mail server

web server etc

Installing Red Hat Enterprise Linux 5

This appendix is straightforward It illustrates the steps required to install Red Hat Enterprise

Linux 5 Server on your computer using graphical and text based installation methods Both are

governed by the Red Hat program known as Anaconda

Graphical Installation

To install Red Hat Enterprise Linux 5 on your computer take the following steps

1 Select and insert the media that yoursquoll use to boot the Red Hat Enterprise Linux 5

installation program It can be the first Red Hat Enterprise Linux 5 CD a boot CD

created from the bootiso file from the images directory of the first installation CD or a

boot USB key created from the diskbootimg file from the same directory

2 Power on your system Press the appropriate key typically ESC F12 or DEL to access the

boot menu shown here If a boot menu isnrsquot available yoursquoll need to adjust the boot sequence

in the computer BIOS which you can then use to boot directly from your selected media Set

your computerrsquos BIOS to boot from the first installation CD or USB drive Details vary by PC

Make sure your BIOS saves your changes before you reboot

3 Type linux askmethod when you see the boot

4 Choose a language and select OK

5 Select a keyboard and select OK

6 Set up an NFS installation method and select OK

7 Start configuring your network as shown If you have a DHCP server on your network that

is simplestmdashunless of course yoursquore told to enable static addressing during your exam For

this installation disable DHCP for both IPv4 and IPv6addressing If you donrsquot have an IPv6-

capable DHCP server or router disable IPv6 addressing completely Select OK If you enable

DHCP skip the next step

8 Add static address information for your network Use the IP Address Gateway and Name

Server (DNS) addresses associated with your existing network Select OK

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

Is Linux difficult or not

Whether Linux is difficult to learn depends on the person

youre asking Experienced UNIX users will say no because

Linux is an ideal operating system for power-users and

programmers because it has been and is being developed by

such people Everything a good programmer can wish for is

available compilers libraries development and debugging

tools These packages come with every standard Linux

distribution The C-compiler is included for free ndash as opposed

to many UNIX distributions demanding licensing fees for this tool All the documentation and

manuals are there and examples are often included to help you get started in no time It feels

like UNIX and switching between UNIX and Linux is a natural thing In the early days of

Linux being an expert was kind of required to start using the system Those who mastered

Linux felt better than the rest of the lusers who hadnt seen the light yet It was common

practice to tell a beginning user to RTFM (read the manuals) While the manuals were on

every system it was difficult to find the documentation and even if someone did explanations

were in such technical terms that the new user became easily discouraged from learning the

system The Linux-using community started to realize that if Linux was ever to be an important

player on the operating system market there had to be some serious changes in the

accessibility of the system

Linux for non-experienced users

Companies such as RedHat SuSE and Mandriva have sprung up providing packaged Linux

distributions suitable for mass consumption They integrated a great deal of graphical user

interfaces (GUIs) developed by the community in order to ease management of programs and

services As a Linux user today you have all the means of getting to know your system inside

out but it is no longer necessary to have that knowledge in order to make the system comply to

your requests

Now a days you can log in graphically and start all required applications without even having

to type a single character while you still have the ability to access the core of the system if

needed Because of its structure Linux allows a user to grow into the system it equally fits

new and experienced users New users are not forced to do difficult things while experienced

users are not forced to work in the same way they did when they first started learning Linux

While development in the service area continues great things are being done for desktop users

generally considered as the group least likely to know how a system works Developers of

desktop applications are making incredible efforts to make the most beautiful desktops youve

ever seen or to make your Linux machine look just like your former MS Windows or an Apple

workstation The latest developments also include 3D acceleration support and support for

USB devices single-click updates of system and packages and so on Linux has these and

tries to present all available services in a logical form that ordinary people can understand

Structures of UNIX LINUX

The highlighting features of this operating system are

(i) Portable ndash Written in C language

(ii) Source code is available in high level language(C )

(iii) Multi-user system implements Time-sharing

(iv) Powerful-defines the concept of power as not the programs but the interaction of programs

The structure of UNIX is as follows

Most prominent are

1 Red Hat LINUX ndash Educational and commercial

2 Caldera LINUX ndash Business oriented

3 SUSE LINUX ndash Retailers and applications

4 Turbo LINUX ndash Multilanguage

5 Debian LINUX ndash Truly free no commercial version

6 Slackware LINUX ndash Most UNIX like

Kernel Version

First official version was 002 and first stable version was 10 As per changes kernel goes

through a

(i) Development phase where lot of changes and modifications are being added and

developed It is denoted by odd number in the versions eg 11 21 etc

(ii) Stabilization phase where small modifications are made to the kernel It is denoted by even

numbers in the versions eg 12 22 Current stable kernel is 2210

Hence Linux architecture as simplified can be seen as-

A seed like core or the kernel which performs rapid switching between tasks under execution

attaches drivers to the few hardware processes inter-process communication prevents

interference with one-another and protects itself from corrupt program routines This kernel

while running grows into a fully Blown OS Linux shell to provide a powerful user interface

while still protecting itself from user-mode unauthorized access It provides the user an

environment to work upon and take ownership of it by customizing it

FEATURErsquoS OF LINUX

MULTI-TASKING In Linux it is possible to have many programs running at

the same time which means that not only can you have many programs going at

once but that the Linux operating system can self have programs running in the

background (and this is the main reason why Linux is used as server)So that

back-ground processes can run side by side These processes are called

DIEMANS

MULTI-USER Not only can you have many user accounts available on a

Linux system you can also have multiple logged in and working on the system

at the same time Users can have their own environment arranged in the way

they want and there own desktop interfaces with icons menus and

applications User accounts can be password protected

GRAPHICAL USER INTERFACE The framework for working with

graphical application in Linux is known as X-windows system or simply X

The X based desktop environment provides the look and feel of GUI Icons

menus themes etc

HARDWARE SUPPORT Linux can configure support for almost every kind

of hardware that can be connected to a computer

NETWORKING CONNECTIVITY To connect a Linux system to a network

Linux offer support for a variety of local area network bolts modems and

serial devices

NETWORK SERVER Linux is the best for providing networking services to

the client computer on RAM or the entire

internet Therefore Linux can be used to act

a print server file server mail server

web server etc

Installing Red Hat Enterprise Linux 5

This appendix is straightforward It illustrates the steps required to install Red Hat Enterprise

Linux 5 Server on your computer using graphical and text based installation methods Both are

governed by the Red Hat program known as Anaconda

Graphical Installation

To install Red Hat Enterprise Linux 5 on your computer take the following steps

1 Select and insert the media that yoursquoll use to boot the Red Hat Enterprise Linux 5

installation program It can be the first Red Hat Enterprise Linux 5 CD a boot CD

created from the bootiso file from the images directory of the first installation CD or a

boot USB key created from the diskbootimg file from the same directory

2 Power on your system Press the appropriate key typically ESC F12 or DEL to access the

boot menu shown here If a boot menu isnrsquot available yoursquoll need to adjust the boot sequence

in the computer BIOS which you can then use to boot directly from your selected media Set

your computerrsquos BIOS to boot from the first installation CD or USB drive Details vary by PC

Make sure your BIOS saves your changes before you reboot

3 Type linux askmethod when you see the boot

4 Choose a language and select OK

5 Select a keyboard and select OK

6 Set up an NFS installation method and select OK

7 Start configuring your network as shown If you have a DHCP server on your network that

is simplestmdashunless of course yoursquore told to enable static addressing during your exam For

this installation disable DHCP for both IPv4 and IPv6addressing If you donrsquot have an IPv6-

capable DHCP server or router disable IPv6 addressing completely Select OK If you enable

DHCP skip the next step

8 Add static address information for your network Use the IP Address Gateway and Name

Server (DNS) addresses associated with your existing network Select OK

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

Linux for non-experienced users

Companies such as RedHat SuSE and Mandriva have sprung up providing packaged Linux

distributions suitable for mass consumption They integrated a great deal of graphical user

interfaces (GUIs) developed by the community in order to ease management of programs and

services As a Linux user today you have all the means of getting to know your system inside

out but it is no longer necessary to have that knowledge in order to make the system comply to

your requests

Now a days you can log in graphically and start all required applications without even having

to type a single character while you still have the ability to access the core of the system if

needed Because of its structure Linux allows a user to grow into the system it equally fits

new and experienced users New users are not forced to do difficult things while experienced

users are not forced to work in the same way they did when they first started learning Linux

While development in the service area continues great things are being done for desktop users

generally considered as the group least likely to know how a system works Developers of

desktop applications are making incredible efforts to make the most beautiful desktops youve

ever seen or to make your Linux machine look just like your former MS Windows or an Apple

workstation The latest developments also include 3D acceleration support and support for

USB devices single-click updates of system and packages and so on Linux has these and

tries to present all available services in a logical form that ordinary people can understand

Structures of UNIX LINUX

The highlighting features of this operating system are

(i) Portable ndash Written in C language

(ii) Source code is available in high level language(C )

(iii) Multi-user system implements Time-sharing

(iv) Powerful-defines the concept of power as not the programs but the interaction of programs

The structure of UNIX is as follows

Most prominent are

1 Red Hat LINUX ndash Educational and commercial

2 Caldera LINUX ndash Business oriented

3 SUSE LINUX ndash Retailers and applications

4 Turbo LINUX ndash Multilanguage

5 Debian LINUX ndash Truly free no commercial version

6 Slackware LINUX ndash Most UNIX like

Kernel Version

First official version was 002 and first stable version was 10 As per changes kernel goes

through a

(i) Development phase where lot of changes and modifications are being added and

developed It is denoted by odd number in the versions eg 11 21 etc

(ii) Stabilization phase where small modifications are made to the kernel It is denoted by even

numbers in the versions eg 12 22 Current stable kernel is 2210

Hence Linux architecture as simplified can be seen as-

A seed like core or the kernel which performs rapid switching between tasks under execution

attaches drivers to the few hardware processes inter-process communication prevents

interference with one-another and protects itself from corrupt program routines This kernel

while running grows into a fully Blown OS Linux shell to provide a powerful user interface

while still protecting itself from user-mode unauthorized access It provides the user an

environment to work upon and take ownership of it by customizing it

FEATURErsquoS OF LINUX

MULTI-TASKING In Linux it is possible to have many programs running at

the same time which means that not only can you have many programs going at

once but that the Linux operating system can self have programs running in the

background (and this is the main reason why Linux is used as server)So that

back-ground processes can run side by side These processes are called

DIEMANS

MULTI-USER Not only can you have many user accounts available on a

Linux system you can also have multiple logged in and working on the system

at the same time Users can have their own environment arranged in the way

they want and there own desktop interfaces with icons menus and

applications User accounts can be password protected

GRAPHICAL USER INTERFACE The framework for working with

graphical application in Linux is known as X-windows system or simply X

The X based desktop environment provides the look and feel of GUI Icons

menus themes etc

HARDWARE SUPPORT Linux can configure support for almost every kind

of hardware that can be connected to a computer

NETWORKING CONNECTIVITY To connect a Linux system to a network

Linux offer support for a variety of local area network bolts modems and

serial devices

NETWORK SERVER Linux is the best for providing networking services to

the client computer on RAM or the entire

internet Therefore Linux can be used to act

a print server file server mail server

web server etc

Installing Red Hat Enterprise Linux 5

This appendix is straightforward It illustrates the steps required to install Red Hat Enterprise

Linux 5 Server on your computer using graphical and text based installation methods Both are

governed by the Red Hat program known as Anaconda

Graphical Installation

To install Red Hat Enterprise Linux 5 on your computer take the following steps

1 Select and insert the media that yoursquoll use to boot the Red Hat Enterprise Linux 5

installation program It can be the first Red Hat Enterprise Linux 5 CD a boot CD

created from the bootiso file from the images directory of the first installation CD or a

boot USB key created from the diskbootimg file from the same directory

2 Power on your system Press the appropriate key typically ESC F12 or DEL to access the

boot menu shown here If a boot menu isnrsquot available yoursquoll need to adjust the boot sequence

in the computer BIOS which you can then use to boot directly from your selected media Set

your computerrsquos BIOS to boot from the first installation CD or USB drive Details vary by PC

Make sure your BIOS saves your changes before you reboot

3 Type linux askmethod when you see the boot

4 Choose a language and select OK

5 Select a keyboard and select OK

6 Set up an NFS installation method and select OK

7 Start configuring your network as shown If you have a DHCP server on your network that

is simplestmdashunless of course yoursquore told to enable static addressing during your exam For

this installation disable DHCP for both IPv4 and IPv6addressing If you donrsquot have an IPv6-

capable DHCP server or router disable IPv6 addressing completely Select OK If you enable

DHCP skip the next step

8 Add static address information for your network Use the IP Address Gateway and Name

Server (DNS) addresses associated with your existing network Select OK

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

Structures of UNIX LINUX

The highlighting features of this operating system are

(i) Portable ndash Written in C language

(ii) Source code is available in high level language(C )

(iii) Multi-user system implements Time-sharing

(iv) Powerful-defines the concept of power as not the programs but the interaction of programs

The structure of UNIX is as follows

Most prominent are

1 Red Hat LINUX ndash Educational and commercial

2 Caldera LINUX ndash Business oriented

3 SUSE LINUX ndash Retailers and applications

4 Turbo LINUX ndash Multilanguage

5 Debian LINUX ndash Truly free no commercial version

6 Slackware LINUX ndash Most UNIX like

Kernel Version

First official version was 002 and first stable version was 10 As per changes kernel goes

through a

(i) Development phase where lot of changes and modifications are being added and

developed It is denoted by odd number in the versions eg 11 21 etc

(ii) Stabilization phase where small modifications are made to the kernel It is denoted by even

numbers in the versions eg 12 22 Current stable kernel is 2210

Hence Linux architecture as simplified can be seen as-

A seed like core or the kernel which performs rapid switching between tasks under execution

attaches drivers to the few hardware processes inter-process communication prevents

interference with one-another and protects itself from corrupt program routines This kernel

while running grows into a fully Blown OS Linux shell to provide a powerful user interface

while still protecting itself from user-mode unauthorized access It provides the user an

environment to work upon and take ownership of it by customizing it

FEATURErsquoS OF LINUX

MULTI-TASKING In Linux it is possible to have many programs running at

the same time which means that not only can you have many programs going at

once but that the Linux operating system can self have programs running in the

background (and this is the main reason why Linux is used as server)So that

back-ground processes can run side by side These processes are called

DIEMANS

MULTI-USER Not only can you have many user accounts available on a

Linux system you can also have multiple logged in and working on the system

at the same time Users can have their own environment arranged in the way

they want and there own desktop interfaces with icons menus and

applications User accounts can be password protected

GRAPHICAL USER INTERFACE The framework for working with

graphical application in Linux is known as X-windows system or simply X

The X based desktop environment provides the look and feel of GUI Icons

menus themes etc

HARDWARE SUPPORT Linux can configure support for almost every kind

of hardware that can be connected to a computer

NETWORKING CONNECTIVITY To connect a Linux system to a network

Linux offer support for a variety of local area network bolts modems and

serial devices

NETWORK SERVER Linux is the best for providing networking services to

the client computer on RAM or the entire

internet Therefore Linux can be used to act

a print server file server mail server

web server etc

Installing Red Hat Enterprise Linux 5

This appendix is straightforward It illustrates the steps required to install Red Hat Enterprise

Linux 5 Server on your computer using graphical and text based installation methods Both are

governed by the Red Hat program known as Anaconda

Graphical Installation

To install Red Hat Enterprise Linux 5 on your computer take the following steps

1 Select and insert the media that yoursquoll use to boot the Red Hat Enterprise Linux 5

installation program It can be the first Red Hat Enterprise Linux 5 CD a boot CD

created from the bootiso file from the images directory of the first installation CD or a

boot USB key created from the diskbootimg file from the same directory

2 Power on your system Press the appropriate key typically ESC F12 or DEL to access the

boot menu shown here If a boot menu isnrsquot available yoursquoll need to adjust the boot sequence

in the computer BIOS which you can then use to boot directly from your selected media Set

your computerrsquos BIOS to boot from the first installation CD or USB drive Details vary by PC

Make sure your BIOS saves your changes before you reboot

3 Type linux askmethod when you see the boot

4 Choose a language and select OK

5 Select a keyboard and select OK

6 Set up an NFS installation method and select OK

7 Start configuring your network as shown If you have a DHCP server on your network that

is simplestmdashunless of course yoursquore told to enable static addressing during your exam For

this installation disable DHCP for both IPv4 and IPv6addressing If you donrsquot have an IPv6-

capable DHCP server or router disable IPv6 addressing completely Select OK If you enable

DHCP skip the next step

8 Add static address information for your network Use the IP Address Gateway and Name

Server (DNS) addresses associated with your existing network Select OK

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

Kernel Version

First official version was 002 and first stable version was 10 As per changes kernel goes

through a

(i) Development phase where lot of changes and modifications are being added and

developed It is denoted by odd number in the versions eg 11 21 etc

(ii) Stabilization phase where small modifications are made to the kernel It is denoted by even

numbers in the versions eg 12 22 Current stable kernel is 2210

Hence Linux architecture as simplified can be seen as-

A seed like core or the kernel which performs rapid switching between tasks under execution

attaches drivers to the few hardware processes inter-process communication prevents

interference with one-another and protects itself from corrupt program routines This kernel

while running grows into a fully Blown OS Linux shell to provide a powerful user interface

while still protecting itself from user-mode unauthorized access It provides the user an

environment to work upon and take ownership of it by customizing it

FEATURErsquoS OF LINUX

MULTI-TASKING In Linux it is possible to have many programs running at

the same time which means that not only can you have many programs going at

once but that the Linux operating system can self have programs running in the

background (and this is the main reason why Linux is used as server)So that

back-ground processes can run side by side These processes are called

DIEMANS

MULTI-USER Not only can you have many user accounts available on a

Linux system you can also have multiple logged in and working on the system

at the same time Users can have their own environment arranged in the way

they want and there own desktop interfaces with icons menus and

applications User accounts can be password protected

GRAPHICAL USER INTERFACE The framework for working with

graphical application in Linux is known as X-windows system or simply X

The X based desktop environment provides the look and feel of GUI Icons

menus themes etc

HARDWARE SUPPORT Linux can configure support for almost every kind

of hardware that can be connected to a computer

NETWORKING CONNECTIVITY To connect a Linux system to a network

Linux offer support for a variety of local area network bolts modems and

serial devices

NETWORK SERVER Linux is the best for providing networking services to

the client computer on RAM or the entire

internet Therefore Linux can be used to act

a print server file server mail server

web server etc

Installing Red Hat Enterprise Linux 5

This appendix is straightforward It illustrates the steps required to install Red Hat Enterprise

Linux 5 Server on your computer using graphical and text based installation methods Both are

governed by the Red Hat program known as Anaconda

Graphical Installation

To install Red Hat Enterprise Linux 5 on your computer take the following steps

1 Select and insert the media that yoursquoll use to boot the Red Hat Enterprise Linux 5

installation program It can be the first Red Hat Enterprise Linux 5 CD a boot CD

created from the bootiso file from the images directory of the first installation CD or a

boot USB key created from the diskbootimg file from the same directory

2 Power on your system Press the appropriate key typically ESC F12 or DEL to access the

boot menu shown here If a boot menu isnrsquot available yoursquoll need to adjust the boot sequence

in the computer BIOS which you can then use to boot directly from your selected media Set

your computerrsquos BIOS to boot from the first installation CD or USB drive Details vary by PC

Make sure your BIOS saves your changes before you reboot

3 Type linux askmethod when you see the boot

4 Choose a language and select OK

5 Select a keyboard and select OK

6 Set up an NFS installation method and select OK

7 Start configuring your network as shown If you have a DHCP server on your network that

is simplestmdashunless of course yoursquore told to enable static addressing during your exam For

this installation disable DHCP for both IPv4 and IPv6addressing If you donrsquot have an IPv6-

capable DHCP server or router disable IPv6 addressing completely Select OK If you enable

DHCP skip the next step

8 Add static address information for your network Use the IP Address Gateway and Name

Server (DNS) addresses associated with your existing network Select OK

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

FEATURErsquoS OF LINUX

MULTI-TASKING In Linux it is possible to have many programs running at

the same time which means that not only can you have many programs going at

once but that the Linux operating system can self have programs running in the

background (and this is the main reason why Linux is used as server)So that

back-ground processes can run side by side These processes are called

DIEMANS

MULTI-USER Not only can you have many user accounts available on a

Linux system you can also have multiple logged in and working on the system

at the same time Users can have their own environment arranged in the way

they want and there own desktop interfaces with icons menus and

applications User accounts can be password protected

GRAPHICAL USER INTERFACE The framework for working with

graphical application in Linux is known as X-windows system or simply X

The X based desktop environment provides the look and feel of GUI Icons

menus themes etc

HARDWARE SUPPORT Linux can configure support for almost every kind

of hardware that can be connected to a computer

NETWORKING CONNECTIVITY To connect a Linux system to a network

Linux offer support for a variety of local area network bolts modems and

serial devices

NETWORK SERVER Linux is the best for providing networking services to

the client computer on RAM or the entire

internet Therefore Linux can be used to act

a print server file server mail server

web server etc

Installing Red Hat Enterprise Linux 5

This appendix is straightforward It illustrates the steps required to install Red Hat Enterprise

Linux 5 Server on your computer using graphical and text based installation methods Both are

governed by the Red Hat program known as Anaconda

Graphical Installation

To install Red Hat Enterprise Linux 5 on your computer take the following steps

1 Select and insert the media that yoursquoll use to boot the Red Hat Enterprise Linux 5

installation program It can be the first Red Hat Enterprise Linux 5 CD a boot CD

created from the bootiso file from the images directory of the first installation CD or a

boot USB key created from the diskbootimg file from the same directory

2 Power on your system Press the appropriate key typically ESC F12 or DEL to access the

boot menu shown here If a boot menu isnrsquot available yoursquoll need to adjust the boot sequence

in the computer BIOS which you can then use to boot directly from your selected media Set

your computerrsquos BIOS to boot from the first installation CD or USB drive Details vary by PC

Make sure your BIOS saves your changes before you reboot

3 Type linux askmethod when you see the boot

4 Choose a language and select OK

5 Select a keyboard and select OK

6 Set up an NFS installation method and select OK

7 Start configuring your network as shown If you have a DHCP server on your network that

is simplestmdashunless of course yoursquore told to enable static addressing during your exam For

this installation disable DHCP for both IPv4 and IPv6addressing If you donrsquot have an IPv6-

capable DHCP server or router disable IPv6 addressing completely Select OK If you enable

DHCP skip the next step

8 Add static address information for your network Use the IP Address Gateway and Name

Server (DNS) addresses associated with your existing network Select OK

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

Installing Red Hat Enterprise Linux 5

This appendix is straightforward It illustrates the steps required to install Red Hat Enterprise

Linux 5 Server on your computer using graphical and text based installation methods Both are

governed by the Red Hat program known as Anaconda

Graphical Installation

To install Red Hat Enterprise Linux 5 on your computer take the following steps

1 Select and insert the media that yoursquoll use to boot the Red Hat Enterprise Linux 5

installation program It can be the first Red Hat Enterprise Linux 5 CD a boot CD

created from the bootiso file from the images directory of the first installation CD or a

boot USB key created from the diskbootimg file from the same directory

2 Power on your system Press the appropriate key typically ESC F12 or DEL to access the

boot menu shown here If a boot menu isnrsquot available yoursquoll need to adjust the boot sequence

in the computer BIOS which you can then use to boot directly from your selected media Set

your computerrsquos BIOS to boot from the first installation CD or USB drive Details vary by PC

Make sure your BIOS saves your changes before you reboot

3 Type linux askmethod when you see the boot

4 Choose a language and select OK

5 Select a keyboard and select OK

6 Set up an NFS installation method and select OK

7 Start configuring your network as shown If you have a DHCP server on your network that

is simplestmdashunless of course yoursquore told to enable static addressing during your exam For

this installation disable DHCP for both IPv4 and IPv6addressing If you donrsquot have an IPv6-

capable DHCP server or router disable IPv6 addressing completely Select OK If you enable

DHCP skip the next step

8 Add static address information for your network Use the IP Address Gateway and Name

Server (DNS) addresses associated with your existing network Select OK

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

3 Type linux askmethod when you see the boot

4 Choose a language and select OK

5 Select a keyboard and select OK

6 Set up an NFS installation method and select OK

7 Start configuring your network as shown If you have a DHCP server on your network that

is simplestmdashunless of course yoursquore told to enable static addressing during your exam For

this installation disable DHCP for both IPv4 and IPv6addressing If you donrsquot have an IPv6-

capable DHCP server or router disable IPv6 addressing completely Select OK If you enable

DHCP skip the next step

8 Add static address information for your network Use the IP Address Gateway and Name

Server (DNS) addresses associated with your existing network Select OK

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

6 Set up an NFS installation method and select OK

7 Start configuring your network as shown If you have a DHCP server on your network that

is simplestmdashunless of course yoursquore told to enable static addressing during your exam For

this installation disable DHCP for both IPv4 and IPv6addressing If you donrsquot have an IPv6-

capable DHCP server or router disable IPv6 addressing completely Select OK If you enable

DHCP skip the next step

8 Add static address information for your network Use the IP Address Gateway and Name

Server (DNS) addresses associated with your existing network Select OK

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

7 Start configuring your network as shown If you have a DHCP server on your network that

is simplestmdashunless of course yoursquore told to enable static addressing during your exam For

this installation disable DHCP for both IPv4 and IPv6addressing If you donrsquot have an IPv6-

capable DHCP server or router disable IPv6 addressing completely Select OK If you enable

DHCP skip the next step

8 Add static address information for your network Use the IP Address Gateway and Name

Server (DNS) addresses associated with your existing network Select OK

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

9 Add connection information to the installation server If you donrsquot have a DNS server for the

local network you can substitute the IP address for the NFS server name Select OK

10 Assuming your connection works yoursquoll see the first installation screen Click Next

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

11 Yoursquove already selected a language and keyboard so the next step if yoursquore actually

running Red Hat Enterprise Linux 5 (as opposed to one of there build distributions) is to enter

an installation number associated with your purchased or trial subscription as shown next The

subscription configures a custom set of package groups and repositories If you donrsquot have an

installation number select the Skip Entering Installation Number radio button Click OK and

If you did not enter an installation number yoursquoll be given a warning Click Skip to continue

12 The installation program searches for existing installations If found yoursquore prompted to

either upgrade or install over the existing installation If not found you wonrsquot see the screen

shown here if the drive is unformatted yoursquoll get a warning Otherwise skip to the next step

Select Install Red Hat Enterprise Server and click Next to continue

13 You can allow Anaconda to configure an optimized partition configuration based on your

memory and available hard disk space (based on free spaceafter removing partitions) or

choose to customize the configuration as shown next For the purpose of this installation

select Review And Modify Partitioning LayoutIf you have network attached storage (NAS)

that is configured to communicate via iSCSI (a TCPIP protocol) click Advanced Storage

Configuration You can also configure communication with that storage here If thatrsquos what

you want to do select Add iSCSI target and click Add Drive This opens a Configure iSCSI

Parameters window where yoursquod enter the IP address and iSCSI Initiator Name But thatrsquos

beyond the scope of the current Red Hat exams Click Cancel to return to the previous screen

and then click Next

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

14 If there are existing partitions on the installed hard drives yoursquoll get the chance

to confirm that you want to remove said partitions (this step isnrsquot final) If yoursquore configuring a

dual-boot with another operating system donrsquot delete the partitions Instead click Back and

select Create A Custom Layout However the Red Hat exams are Linux exams so I believe a

dual-boot configuration especially with Microsoft Windows is unlikely during the exam

These options are shown next Choose Yes or No as appropriate

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

15 Now inspect and change partitions in Disk Druid as shown You can also create and then

configure RAID and LVM partitionsMake any desired changes and then click Next

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

16 Once yoursquove configured your partitions set up a boot loader If you select No Boot Loader

Will Be Installed yoursquoll need to use a third-party boot loader such as Partition Magic or

Microsoftrsquos NTLDR Unless you want to set up a Boot Loader Password or Configure

Advanced Boot Loader Options click Next

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

17 Configure your connection to the network It should reflect the settings you input in steps 8

and possibly 9 If you donrsquot want the DHCP server to assign a hostname (or you donrsquot have a

DHCP server) you can assign it manually as shown here Click Next to move on

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

18 Set the time zone for your system If you donrsquot have another operating system on this

computer keep the System Clock Uses UTC option active Then click Next

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

19 Type in and confirm the root password for your system Follow any instructions on your

exam carefully for this you want to make it easy for the person grading your exam to see what

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

yoursquove done Yes lost root passwords can be reset but what will your score be if the person

grading your exam finds that you ignored his or her instructions Click Next

20 There are two package customization screens available Everyone sees the screen shown

next (The choices are slightly different for Red Hat Enterprise Linux 5 Client) You can accept

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

the defaults select available options andor select Customize Now Itrsquos usually best to

customize modestly (Irsquove selected the Customize Now option) based on the requirements on

your particular Installation and Configuration exam Click Next (If you donrsquot select Customize

Now skip the next step)

21 Select the package groups of your choice This should conform to the requirements of the

Installation and Configuration section of your particular exam Click Next

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

22 Once yoursquove selected the package groups of your choice you get one last chance to go

back before starting the installation process Click Next if yoursquore happy with your choices or

click Back to make changes

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

23 Some configuration options associated with previous versions of RHEL are no longer part

of the installation process Some of these options are part of the First Boot process described in

Chapter 2 Normally yoursquoll see the First Boot screens only the first time you reboot a system

Click Next when yoursquore ready to start the actual installation process Depending on hardware

and network connections it may take a few minutes or more

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

24 The next screen congratulates you for completing the installation The next step is to reboot

your computer into RHEL Click Reboot If you had to modify your computerrsquos BIOS menu

change it back so it boots from the hard drive in the future Make sure your BIOS saves your

changes before you reboot

Directory Structure of Linux

These are the basic directories that you (should) have after

installing any Linux distribution Root() is the frist components

which install firstly when we install Linux in the computer and also

execute first when we start Linux Directory structures of Linux as

following directories

bin

dev

etc

home

lib

mnt

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

proc

root

sbin

tmp

usr

var

bin

This is where all your programs that are accessible to all users will be stored once installed

dev

This is a virtual directory where your devices are stored Devfs allows Linux to list devices

(hard drives input devices modems sound cards etc) as files

etc

This is where youll find all your global settings Daemons such as ssh telnet and smtppop3

mail servers find their configuration files here Also in etc is the systems password file group

lists user skeletons and cron jobs

home

This is the default directory where non-root users homes are created When you add a user the

default home directory is created as homeusername You can change this default in the proper

file in etc

lib

This is where shared libraries (perl python C etc) are stored Also in lib are your kernel

modules

mnt

This is the default location for mounting cdroms floppy disk drives USB memory sticks etc

You can mount anything anywhere but by default there is a mntfloppy (if you have a floppy

drive) and mntcdrom

proc

This virtual folder contains information about your system You can view processor

statisticsspecifications PCI bus information ISA bus information and pretty much anything

else you want to know about the hardware on your system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

root

This is the default home directory for the user root

sbin

This is where system programs are installed These include fdisk tools to make partitions

certain network tools and other things that normal users shouldnt have a need for

tmp

This is the default location to place files for temporary use When you install a program it uses

tmp to put files during installation that wont be needed once the program is installed

usr

This contains various programs non-daemon program settings and program resources

Linux Shell Commands

Command shell

A program that interprets commands 1048576 Allows a user to execute commands by typing them

manually at a terminal or automatically in programs called shell scripts 1048576 A shell is not an

operating system It is a way to interface with the operating system and run Commands

What is BASH

BASH = Bourne Again Shell Bash is a shell written as a free replacement to the standard

Bourne Shell (binsh) originally written by Steve Bourne for UNIX systems It has all of the

features of the original Bourne Shell plus additions that make it easier to program with and use

from the command line Since it is Free Software it has been adopted as the default shell on

most Linux systems

Linux Basic Commands

MKDIR -

This command is used for creating directory in the Linux

SYNTAX

$ mkdir dir name

CD -

This command is used for changing directory

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

SYNTAX

$ cdltdir namegt

PWD -

This command is used for displaying the present working directory

SYNTAX

$pwd

TOUCH -

This command create an empty file

SYNTAX

$ touchltfile namegt

CAT -

This command is used for creating reading writing appending a file

SYNTAX

$catltfile namegt

CP -

This command is used for copying a file from source to destination

SYNTAX

$cp ltsourcepathgt ltdestination pathgt

MV -

This command is used for moving a perticuler file from one memory location to other This command can also be used for renaming a file This command can also be used for overwriting a file

SYNTAX

$ mv ltsource filegt ltdirectory namegt

RM -

This command is used for removing a file directory sud-directories

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

SYNTAX

$rm ltfile namegt ltdirectory namegt

RM-i -

This command is used for removing file interactively ie before deleting files it would confirm it from user

SYNTAX

$ rm-I ltdir namegt

RMDIR -

This command is used for removing directory but before removing the directory you must assure that the directory is empty ie there is no sub-directory or file in it

SYNTAX

$ rmdir ltdir namegt

LS -

This command is used for displaying all the files and sub-directories of present working directories

SYNTAX

$ ls

Ls-a display all hidden files of present working directory

Ls-l display list of file and sub-directories of present working directories

MAN-

This command is used for displaying the full descriptions of any command

SYNTAX

$manltcommand namegt

UMASK-

This command is used to display the default permission of the file

SYNTAX-

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

$umask

CHMOD-

This command is used for chaning mode of the file

SYNTAX

chmodltmodegtltfilenamegt

LOGNAME-

This command is used for displaying the login name

SYNTAX

$logname

UNAME-

This command is used for displaying the version of the linux

SYNTAX

$uname

PASSWD-

This command is used for chaning the current password of current user

SYNTAX

$passwd

WHO-

this command is used for numbersnamesof the connected dumb terminals

SYNTAX

$who

WHO AM I-

This command is used for displaying the details of yours terminals

SYNTAX

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

$ whami

Partition of Hard Disk in Linux using Fdisk

In the Linux we can partition the hard disk using fdisk command Linux support the file system ext2 and ext3 by default but we can also used fat file system in Linux

Fdisk usage

Frist to see the all partition made already type following command

fdisk ndashl

It will show all partition made in linux

fdisk is started by typing (as root) fdisk device at the command prompt device might be something like devhda or devsda

fdisk devsda (for Sata Hard disk)

fdisk devhda (for IDE Hard disk)

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

After using upper command use following basic fdisk commands you need are

p print the partition table

n create a new partition

d delete a partition

q quit without saving changes

w write the new partition table and exit

Changes you make to the partition table do not take effect until you issue the write (w) command Here is a sample partition table

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 184 370912+ 83 Linuxdevhdb2 185 368 370944 83 Linuxdevhdb3 369 552 370944 83 Linuxdevhdb4 553 621 139104 82 Linux swap

Creating Three primary partitions with one Swap

The overview

Decide on the size of your swap space and where it ought to go Divide up the remaining space for the three other partitions

Example

I start fdisk from the shell prompt

fdisk devhdb

which indicates that I am using the second drive on my IDE controller When I print the partition table I just get configuration information

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

Command (m for help) p

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes

I knew that I had a 12Gb drive but now I really know 64 63 512 621 = 1281982464

bytes I decide to reserve 128Mb of that space for swap leaving 1153982464 If I use one of

my primary partitions for swap that means I have three left for ext2 partitions Divided

equally that makes for 384Mb per partition Now I get to work

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 1First cylinder (1-621 default 1)ltRETURNgtUsing default value 1Last cylinder or +size or +sizeM or +sizeK (1-621 default 621) +384M

Next I set up the partition I want to use for swap

Command (m for help) nCommand action e extended p primary partition (1-4)pPartition number (1-4) 2First cylinder (197-621 default 197)ltRETURNgtUsing default value 197Last cylinder or +size or +sizeM or +sizeK (197-621 default 621) +128M

Now the partition table looks like this

Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104 83 Linuxdevhdb2 197 262 133056 83 Linux

I set up the remaining two partitions the same way I did the first Finally I make the first partition bootable

Command (m for help) aPartition number (1-4) 1

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

And I make the second partition of type swap

Command (m for help) tPartition number (1-4) 2Hex code (type L to list codes) 82Changed system type of partition 2 to 82 (Linux swap) Command (m for help) p

The end result

Disk devhdb 64 heads 63 sectors 621 cylindersUnits = cylinders of 4032 512 bytes Device Boot Start End Blocks Id Systemdevhdb1 1 196 395104+ 83 Linuxdevhdb2 197 262 133056 82 Linux swapdevhdb3 263 458 395136 83 Linuxdevhdb4 459 621 328608 83 Linux

Finally I issue the write command (w) to write the table on the disk

After doing the partition please reboot the computer or user following command to refresh the partition hard disk

partprobe devhda

Formatting the partition in Linux

After creating the partition you need to format the partition for using the space Linux defaults

using the ext2 or ext3 file system but we can also used fat file system in Linux

1 For format the partitation in ext3 file system use

following commands

mke2fs ndashj devhda4

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

2 For format the partitation in ext2 file system use

following commands

mke2fs devhda4

3 For format the partitation in FAT file system use

following commands

mke2fs vfat devhda4

Mounting the Partition

mount attaches the filesystem specified by source (which is often a device name but can also

be a directory name or a dummy) to the directory specified by target umount and umount2

remove the attachment of the (topmost) filesystem mounted on target Only the super-user may

mount and unmount filesystems Since Linux 24 a single filesystem can be visible at multiple

mount points and multiple mounts can be stacked on the same mount point In linux we can

not use the space in the partition directly first we mount the partition on one directory and

then we can user the space (directory space) to mount the partition the use the following

commands

Mount the partition

mount devhda4 Songs

Command Partition Address of directory

Mounting the CDROM in Linux

mount devcdrom media

Command Device Address Address of partition (on which mounted)

The upper commands will mount the partition temporary for mount partition we enter the detail of partition in fstab file

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

Umount

it mean un mount the partition form directory This command is used to un mount the partition use this a following

umount devhda4 Songs Command Device Address Address of partition (on which mounted)

After mounting or un mounting the any partition run following command to refresh the fstab file as following

mount ndasha

Fstab file

Fstab File Open by using Vi Editior

vi etcfstab ( command used to open the fstab file )

In the fstab file there are the record of the mounted partition fstab file is placed in the etc directopry and if you mount the partation in any directory and you wants to mount that partation paramantly then add new line in fstab as following syntax

Partation address Directory Address Partition file system 0 0

As Show in upper figure the fstab file is open For example if u want to mount the one partation in the linux parmanently frist mount the partition as using upper mounting command after that you open the fstab file and add new line in it as following the new line is

devsda8 Songs vfat defaults 0 0

After enter the new line save the file and run the command

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

mount ndasha

To refresh the fstab file the partition permanently mounted

Run levels

A runlevel is a preset operating state on a Unix-like operating system A system can be booted

into (ie started up into) any of several runlevels each of which is represented by a single digit

integer Each runlevel designates a different system configuration and allows access to a

different combination of processes (ie instances of executing programs) The are differences

in the runlevels according to the operating system Seven runlevels are supported in the

standard Linux kernel (ie core of the operating system) They are

0 - System halt no activity the system can be safely powered down

init 0

1 - Single user rarely used

init 1

2 - Multiple users no NFS (network filesystem) also used rarely

init 2

3 - Multiple users command line (ie all-text mode) interface the standard runlevel for most Linux-based server hardware

init 3

5 - Multiple users GUI (graphical user interface) the standard runlevel for most Linux-based desktop systems

init 5

6 - Reboot used when restarting the system

init6

Run Levels in Red Hat Linux and Fedora

Red Hat as well as most of its derivatives uses runlevels like

this

By default Linux boots either

to runlevel 3 or to runlevel 5

The former permits the system

to run all services except for a

GUI The latter allows all

services including a GUI In

addition to the standard

runlevels users can modify

the preset runlevels or even

create new ones if desired

Runlevels 2 and 4 are usually

used for user defined

runlevels

Booting into a different

runlevel can help solve certain

problems Likewise if a

machine will not boot due to a

damaged configuration file or

will not allow logging in because of a corrupted etcpasswd file (which stores user names and

other data about users) or because of a forgotten password the problem can solved by first

booting into single-user mode (ie runlevel

How to get access of root

Red Hat LinuxFedora runlevels

Description

0 Halt

1 Single user

2 Not usedUser definable

3 Full multi-user console logins only

4 Not usedUser definable

5Full multi-user with display manager as well as console logins

6 Reboot

Or

Breaking the password

To break the password of the root first start the computer in the single user and trouble

shooting mood (init 0) To start the computer in the init 0 run level do as following

Power on the computer and press esc button to stop the linux on boot screen Press e to open the grub configuration

Select the kernel line and pess e t edit the kernel line

Give the space at the last of line ahe write 1 on it as following rhgb quiet 1

Press enter to save (but this 1 is temparory entered that not save )

Press b to boot the computer again

After rebooting the computer will start in the trouble shooting mode And following type of command promptis shown

Sh 30

There are two type of breaking passwords

1 Assign new password

2 Password stage break

1 Assign new password- by using this we give new password to the user by using the

following commands

Sh 30 passwd

Enter the new password

After give new password run the computer in defaults mode (run level 3) by using

following commands

Sh 30 init 3

1 Password stage break- In this method after breaking the password you no need to

enter any password To do this do as following

Start the Computer in trouble shooting mode as upper

After that open the following file in vi edition

Sh 30 vi etcpassword

All the computer password stored in this file but in encrypted form

In this file remove the X first line

Save the file and exit

Then start the computer in default mode(init 3)

Sh 30 init 3

After the reboot enter the user name root but do not ether the password simple press the enter

and computer will start

RPM Packages installation in Linux

Introduction

RPM is the RPM Package Manager It is an open packaging system available for anyone to use It

allows users to take source code for new software and package it into source and binary form such that

binaries can be easily installed and tracked and source can be rebuilt easily It also maintains a database

of all packages and their files that can be used for verifying packages and querying for information

about files andor packages Red Hat Inc encourages other distribution vendors to take the time to look

at RPM and use it for their own distributions RPM is quite flexible and easy to use though it provides

the base for a very extensive system It is also completely open and available though we would

appreciate bug reports and fixes Permission is granted to use and distribute RPM royalty free under the

GPL

RPM - it stands for red hat package management rpm command is used to manage the package it

also used to install update remove nd query the packages in the Linux

Using RPM

In its simplest form RPM can be used to install packages

rpm minusi foobarminus10minus1i386rpm

The next simplest command is to uninstall a package

rpm minuse foobar

One of the more complex but highly useful commands allows you to install packages via FTP If you

are connected to the net and want to install a new package all you need to do is specify the file with a

valid URL like so

rpm minusi ftpftpredhatcompubredhatrhminus20minusbetaRPMSfoobarminus10minus1i386rpm

Please note that RPM will now query andor install via FTP While these are simple commands rpm

can be used in a multitude of ways To see which options are available in your version of RPM type

rpm ndashhelp

Installing the packages using RPM commands

Start the Computer in trouble shooting mode as upper

After that open the following file in vi edition

Sh 30 vi etcpassword

All the computer password stored in this file but in encrypted form

In this file remove the X first line

Save the file and exit

Then start the computer in default mode(init 3)

Sh 30 init 3

After the reboot enter the user name root but do not ether the password simple press the enter

and computer will start

RPM Packages installation in Linux

Introduction

RPM is the RPM Package Manager It is an open packaging system available for anyone to use It

allows users to take source code for new software and package it into source and binary form such that

binaries can be easily installed and tracked and source can be rebuilt easily It also maintains a database

of all packages and their files that can be used for verifying packages and querying for information

about files andor packages Red Hat Inc encourages other distribution vendors to take the time to look

at RPM and use it for their own distributions RPM is quite flexible and easy to use though it provides

the base for a very extensive system It is also completely open and available though we would

appreciate bug reports and fixes Permission is granted to use and distribute RPM royalty free under the

GPL

RPM - it stands for red hat package management rpm command is used to manage the package it

also used to install update remove nd query the packages in the Linux

Using RPM

In its simplest form RPM can be used to install packages

rpm minusi foobarminus10minus1i386rpm

The next simplest command is to uninstall a package

rpm minuse foobar

One of the more complex but highly useful commands allows you to install packages via FTP If you

are connected to the net and want to install a new package all you need to do is specify the file with a

valid URL like so

rpm minusi ftpftpredhatcompubredhatrhminus20minusbetaRPMSfoobarminus10minus1i386rpm

Please note that RPM will now query andor install via FTP While these are simple commands rpm

can be used in a multitude of ways To see which options are available in your version of RPM type

rpm ndashhelp

Installing the packages using RPM commands

Introduction

RPM is the RPM Package Manager It is an open packaging system available for anyone to use It

allows users to take source code for new software and package it into source and binary form such that

binaries can be easily installed and tracked and source can be rebuilt easily It also maintains a database

of all packages and their files that can be used for verifying packages and querying for information

about files andor packages Red Hat Inc encourages other distribution vendors to take the time to look

at RPM and use it for their own distributions RPM is quite flexible and easy to use though it provides

the base for a very extensive system It is also completely open and available though we would

appreciate bug reports and fixes Permission is granted to use and distribute RPM royalty free under the

GPL

RPM - it stands for red hat package management rpm command is used to manage the package it

also used to install update remove nd query the packages in the Linux

Using RPM

In its simplest form RPM can be used to install packages

rpm minusi foobarminus10minus1i386rpm

The next simplest command is to uninstall a package

rpm minuse foobar

One of the more complex but highly useful commands allows you to install packages via FTP If you

are connected to the net and want to install a new package all you need to do is specify the file with a

valid URL like so

rpm minusi ftpftpredhatcompubredhatrhminus20minusbetaRPMSfoobarminus10minus1i386rpm

Please note that RPM will now query andor install via FTP While these are simple commands rpm

can be used in a multitude of ways To see which options are available in your version of RPM type

rpm ndashhelp

Installing the packages using RPM commands

Examples- if you wants to install the Ddcpf packages in the computer using the rpm command first

open the directory in which the packages is placed and run the following command

rpm ndashivh dhcp --aid ndashforce

Ivh- its mean install in visible mode processing

Aid- add and check install dependcies

Force - ignore error

Updating the packages using RPM commands

If the pacakages is already install and you wants to update the packages with higher version

the use the following commands we update the dhcpd with update packages as following

rpm -uvh dhcpd --aid ndashforce

-uvh- update in visible mode

Query the installed packages

To check the packages is installed or not then use the following commands

rpm ndashqa dhcpd

-qa-query the packages

Removing the packages from linux

rpm ndashe dhcpd ndashnodeps

-nodeps- do not remove dependences

Backup and the Compression

In the Linux extension of the backup file is tar colour of the backup file is always red

To Create the backup of the directory use the following commands

tar cuf backuptar data

Tar- its is an command to put the backup of data

Cuf- its mean create the backup

Backuptar- it is an backup file

Data- it is an source file or directory

To list the files which are in the backup directory run following commands

tar tuf backuptar

Tuf means list the files in the backuptar directory

To restore the backup files

tar data backuptar

Data is the directory where restore the data

Backup is the backup files

DHCP Server in Linux

What is DHCP server

It stands for Dynamic host configuration protocol There may be one or more dhcp peer

network DHCP forwarding agent allows

clients to receive address from dhcp

server which is not part of network

Server can be configured to accept request

from specified MAC address only Dhcp tell

about IP address net mask default

gateway domain name dns server and

location of kick start files

If boot protol at client is BOOTP client will retain their configuration information indefinitely

this is no lease time in BOOTP

To check working of dhcp server boot a machine thru dhcp server then check var logsyslog

of dhcp server

DHCP Service Profile

Type System V-managed Service

Packages dhcp

Daemons dhcpd

Script dhcpd

Ports 67

Configs etcdhcpdconf varlibdhcpdhcpdleases

DHCP Used for

Dynamic host configuration protocol

Providing IP Address Gateway DNS

Working on the Port no 6768

Installation of Dhcp packages for setup the dhcp server

We ca install the packages by tree ways-

1 By using the RPM commands

2 By using the tar Packages (Unix standard)

3 By using the yum Server

1 By using the RPM commands -

The Dhcp packages is available in the linux enterprise edition and you can install it from the

it By using the following commands

Insert the dvd of the Red hat enterprise edition in dvdRom

Mount the cd rom by usingh following commands

mount devcdrom media

After mounting the drive and open media directory and the open the server directory

Install the packages in by using the following rpm commands

The 4 packages are installed after installed the package the copy the sample file in the conf file of the server and do setting of server in the files as following

After copy the file then open the file as show in the below figure

vi etcdhcpdconf

After open the fill all the information in the file according to needs and remove the (comments) from line which you wants to use

In this file fill the following information about network

Router Ip Address Subnet mask used in network Domain server name (if configure) If of the domain name server Range of the ip address which you wants to distributes in the network

After do the upper setting then save the file and exit

Now start and stop service of dhcp

To start the service do following commands

service dhcpd restart

To start the service permanently run following commands

chconfig dhcpd on

To see the status of the server user following commands

talif varlogmessages

To stop the service use following

service dhcpd stop

About FTP

FTP (File Transfer Protocol) is a clientserver protocol that

allows a user to transfer files to and from a remote network

site It works with TCP and is most commonly used on the

Internet although it can also be used on a LAN An FTP site is

a computer that is running FTP server software (also known an

FTP daemon or ftpd) A public ftp site can usually be

accessed by anybody by logging in as anonymous or ftp There are many excellent public ftp

sites that make repositories of free Unix software available By learning how to use FTP you

give yourself access to an indespensible resource Private FTP sites require a user name or

password If you have a shell account with your ISP you may be able to access your files via

FTP (contact your system administrator to check on this) An FTP client is the userland

application that provides access to FTP servers There are many FTP clients available Some

are graphical and some are textminusbased

Short for File Transfer Protocol the protocol for exchanging files over the Internet FTP works

in the same way as HTTP for transferring Web pages from a server to a users browser and

SMTP for transferring electronic mail across the Internet in that like these technologies FTP

rpm ndashqa dhcpd

-qa-query the packages

Removing the packages from linux

rpm ndashe dhcpd ndashnodeps

-nodeps- do not remove dependences

Backup and the Compression

In the Linux extension of the backup file is tar colour of the backup file is always red

To Create the backup of the directory use the following commands

tar cuf backuptar data

Tar- its is an command to put the backup of data

Cuf- its mean create the backup

Backuptar- it is an backup file

Data- it is an source file or directory

To list the files which are in the backup directory run following commands

tar tuf backuptar

Tuf means list the files in the backuptar directory

To restore the backup files

tar data backuptar

Data is the directory where restore the data

Backup is the backup files

DHCP Server in Linux

What is DHCP server

It stands for Dynamic host configuration protocol There may be one or more dhcp peer

network DHCP forwarding agent allows

clients to receive address from dhcp

server which is not part of network

Server can be configured to accept request

from specified MAC address only Dhcp tell

about IP address net mask default

gateway domain name dns server and

location of kick start files

If boot protol at client is BOOTP client will retain their configuration information indefinitely

this is no lease time in BOOTP

To check working of dhcp server boot a machine thru dhcp server then check var logsyslog

of dhcp server

DHCP Service Profile

Type System V-managed Service

Packages dhcp

Daemons dhcpd

Script dhcpd

Ports 67

Configs etcdhcpdconf varlibdhcpdhcpdleases

DHCP Used for

Dynamic host configuration protocol

Providing IP Address Gateway DNS

Working on the Port no 6768

Installation of Dhcp packages for setup the dhcp server

We ca install the packages by tree ways-

1 By using the RPM commands

2 By using the tar Packages (Unix standard)

3 By using the yum Server

1 By using the RPM commands -

The Dhcp packages is available in the linux enterprise edition and you can install it from the

it By using the following commands

Insert the dvd of the Red hat enterprise edition in dvdRom

Mount the cd rom by usingh following commands

mount devcdrom media

After mounting the drive and open media directory and the open the server directory

Install the packages in by using the following rpm commands

The 4 packages are installed after installed the package the copy the sample file in the conf file of the server and do setting of server in the files as following

After copy the file then open the file as show in the below figure

vi etcdhcpdconf

After open the fill all the information in the file according to needs and remove the (comments) from line which you wants to use

In this file fill the following information about network

Router Ip Address Subnet mask used in network Domain server name (if configure) If of the domain name server Range of the ip address which you wants to distributes in the network

After do the upper setting then save the file and exit

Now start and stop service of dhcp

To start the service do following commands

service dhcpd restart

To start the service permanently run following commands

chconfig dhcpd on

To see the status of the server user following commands

talif varlogmessages

To stop the service use following

service dhcpd stop

About FTP

FTP (File Transfer Protocol) is a clientserver protocol that

allows a user to transfer files to and from a remote network

site It works with TCP and is most commonly used on the

Internet although it can also be used on a LAN An FTP site is

a computer that is running FTP server software (also known an

FTP daemon or ftpd) A public ftp site can usually be

accessed by anybody by logging in as anonymous or ftp There are many excellent public ftp

sites that make repositories of free Unix software available By learning how to use FTP you

give yourself access to an indespensible resource Private FTP sites require a user name or

password If you have a shell account with your ISP you may be able to access your files via

FTP (contact your system administrator to check on this) An FTP client is the userland

application that provides access to FTP servers There are many FTP clients available Some

are graphical and some are textminusbased

Short for File Transfer Protocol the protocol for exchanging files over the Internet FTP works

in the same way as HTTP for transferring Web pages from a server to a users browser and

SMTP for transferring electronic mail across the Internet in that like these technologies FTP

Data is the directory where restore the data

Backup is the backup files

DHCP Server in Linux

What is DHCP server

It stands for Dynamic host configuration protocol There may be one or more dhcp peer

network DHCP forwarding agent allows

clients to receive address from dhcp

server which is not part of network

Server can be configured to accept request

from specified MAC address only Dhcp tell

about IP address net mask default

gateway domain name dns server and

location of kick start files

If boot protol at client is BOOTP client will retain their configuration information indefinitely

this is no lease time in BOOTP

To check working of dhcp server boot a machine thru dhcp server then check var logsyslog

of dhcp server

DHCP Service Profile

Type System V-managed Service

Packages dhcp

Daemons dhcpd

Script dhcpd

Ports 67

Configs etcdhcpdconf varlibdhcpdhcpdleases

DHCP Used for

Dynamic host configuration protocol

Providing IP Address Gateway DNS

Working on the Port no 6768

Installation of Dhcp packages for setup the dhcp server

We ca install the packages by tree ways-

1 By using the RPM commands

2 By using the tar Packages (Unix standard)

3 By using the yum Server

1 By using the RPM commands -

The Dhcp packages is available in the linux enterprise edition and you can install it from the

it By using the following commands

Insert the dvd of the Red hat enterprise edition in dvdRom

Mount the cd rom by usingh following commands

mount devcdrom media

After mounting the drive and open media directory and the open the server directory

Install the packages in by using the following rpm commands

The 4 packages are installed after installed the package the copy the sample file in the conf file of the server and do setting of server in the files as following

After copy the file then open the file as show in the below figure

vi etcdhcpdconf

After open the fill all the information in the file according to needs and remove the (comments) from line which you wants to use

In this file fill the following information about network

Router Ip Address Subnet mask used in network Domain server name (if configure) If of the domain name server Range of the ip address which you wants to distributes in the network

After do the upper setting then save the file and exit

Now start and stop service of dhcp

To start the service do following commands

service dhcpd restart

To start the service permanently run following commands

chconfig dhcpd on

To see the status of the server user following commands

talif varlogmessages

To stop the service use following

service dhcpd stop

About FTP

FTP (File Transfer Protocol) is a clientserver protocol that

allows a user to transfer files to and from a remote network

site It works with TCP and is most commonly used on the

Internet although it can also be used on a LAN An FTP site is

a computer that is running FTP server software (also known an

FTP daemon or ftpd) A public ftp site can usually be

accessed by anybody by logging in as anonymous or ftp There are many excellent public ftp

sites that make repositories of free Unix software available By learning how to use FTP you

give yourself access to an indespensible resource Private FTP sites require a user name or

password If you have a shell account with your ISP you may be able to access your files via

FTP (contact your system administrator to check on this) An FTP client is the userland

application that provides access to FTP servers There are many FTP clients available Some

are graphical and some are textminusbased

Short for File Transfer Protocol the protocol for exchanging files over the Internet FTP works

in the same way as HTTP for transferring Web pages from a server to a users browser and

SMTP for transferring electronic mail across the Internet in that like these technologies FTP

Providing IP Address Gateway DNS

Working on the Port no 6768

Installation of Dhcp packages for setup the dhcp server

We ca install the packages by tree ways-

1 By using the RPM commands

2 By using the tar Packages (Unix standard)

3 By using the yum Server

1 By using the RPM commands -

The Dhcp packages is available in the linux enterprise edition and you can install it from the

it By using the following commands

Insert the dvd of the Red hat enterprise edition in dvdRom

Mount the cd rom by usingh following commands

mount devcdrom media

After mounting the drive and open media directory and the open the server directory

Install the packages in by using the following rpm commands

The 4 packages are installed after installed the package the copy the sample file in the conf file of the server and do setting of server in the files as following

After copy the file then open the file as show in the below figure

vi etcdhcpdconf

After open the fill all the information in the file according to needs and remove the (comments) from line which you wants to use

In this file fill the following information about network

Router Ip Address Subnet mask used in network Domain server name (if configure) If of the domain name server Range of the ip address which you wants to distributes in the network

After do the upper setting then save the file and exit

Now start and stop service of dhcp

To start the service do following commands

service dhcpd restart

To start the service permanently run following commands

chconfig dhcpd on

To see the status of the server user following commands

talif varlogmessages

To stop the service use following

service dhcpd stop

About FTP

FTP (File Transfer Protocol) is a clientserver protocol that

allows a user to transfer files to and from a remote network

site It works with TCP and is most commonly used on the

Internet although it can also be used on a LAN An FTP site is

a computer that is running FTP server software (also known an

FTP daemon or ftpd) A public ftp site can usually be

accessed by anybody by logging in as anonymous or ftp There are many excellent public ftp

sites that make repositories of free Unix software available By learning how to use FTP you

give yourself access to an indespensible resource Private FTP sites require a user name or

password If you have a shell account with your ISP you may be able to access your files via

FTP (contact your system administrator to check on this) An FTP client is the userland

application that provides access to FTP servers There are many FTP clients available Some

are graphical and some are textminusbased

Short for File Transfer Protocol the protocol for exchanging files over the Internet FTP works

in the same way as HTTP for transferring Web pages from a server to a users browser and

SMTP for transferring electronic mail across the Internet in that like these technologies FTP

The 4 packages are installed after installed the package the copy the sample file in the conf file of the server and do setting of server in the files as following

After copy the file then open the file as show in the below figure

vi etcdhcpdconf

After open the fill all the information in the file according to needs and remove the (comments) from line which you wants to use

In this file fill the following information about network

Router Ip Address Subnet mask used in network Domain server name (if configure) If of the domain name server Range of the ip address which you wants to distributes in the network

After do the upper setting then save the file and exit

Now start and stop service of dhcp

To start the service do following commands

service dhcpd restart

To start the service permanently run following commands

chconfig dhcpd on

To see the status of the server user following commands

talif varlogmessages

To stop the service use following

service dhcpd stop

About FTP

FTP (File Transfer Protocol) is a clientserver protocol that

allows a user to transfer files to and from a remote network

site It works with TCP and is most commonly used on the

Internet although it can also be used on a LAN An FTP site is

a computer that is running FTP server software (also known an

FTP daemon or ftpd) A public ftp site can usually be

accessed by anybody by logging in as anonymous or ftp There are many excellent public ftp

sites that make repositories of free Unix software available By learning how to use FTP you

give yourself access to an indespensible resource Private FTP sites require a user name or

password If you have a shell account with your ISP you may be able to access your files via

FTP (contact your system administrator to check on this) An FTP client is the userland

application that provides access to FTP servers There are many FTP clients available Some

are graphical and some are textminusbased

Short for File Transfer Protocol the protocol for exchanging files over the Internet FTP works

in the same way as HTTP for transferring Web pages from a server to a users browser and

SMTP for transferring electronic mail across the Internet in that like these technologies FTP

To start the service do following commands

service dhcpd restart

To start the service permanently run following commands

chconfig dhcpd on

To see the status of the server user following commands

talif varlogmessages

To stop the service use following

service dhcpd stop

About FTP

FTP (File Transfer Protocol) is a clientserver protocol that

allows a user to transfer files to and from a remote network

site It works with TCP and is most commonly used on the

Internet although it can also be used on a LAN An FTP site is

a computer that is running FTP server software (also known an

FTP daemon or ftpd) A public ftp site can usually be

accessed by anybody by logging in as anonymous or ftp There are many excellent public ftp

sites that make repositories of free Unix software available By learning how to use FTP you

give yourself access to an indespensible resource Private FTP sites require a user name or

password If you have a shell account with your ISP you may be able to access your files via

FTP (contact your system administrator to check on this) An FTP client is the userland

application that provides access to FTP servers There are many FTP clients available Some

are graphical and some are textminusbased

Short for File Transfer Protocol the protocol for exchanging files over the Internet FTP works

in the same way as HTTP for transferring Web pages from a server to a users browser and

SMTP for transferring electronic mail across the Internet in that like these technologies FTP

uses the Internets TCPIP protocols to enable data transfer FTP is most commonly used to

download a file from a server using the Internet or to upload a file to a server

What is FTP Server

FTP (File Transfer Protocol) is the simplest and most secure way to exchange files over the

Internet Whether you know it or not you most likely use FTP all the time The most common

use for FTP is to download files from the Internet Because of this FTP is the backbone of the

MP3 music craze and vital to most online auction and game enthusiasts In addition the

ability to transfer files back-and-forth makes FTP essential for anyone creating a Web page

amateurs and professionals alike When downloading a file from the Internet youre actually

transferring the file to your computer from another computer over the Internet This is why the

T (transfer) is in FTP You may not know where the computer is that the file is coming from

but you most likely know its URL or Internet address

An FTP address looks a lot like an HTTP or Website address except it uses the prefix ftp

instead of http

Example Website address httpwwwftpplanetcom

Example FTP site address ftpftpftpplanetcom

Types of FTP

From a networking perspective the two main types of FTP are active and passive In active

FTP the FTP server initiates a data transfer connection back to the client For passive FTP the

connection is initiated from the FTP client These are illustrated in Figure

Figure Active And Passive FTP Illustrated

From a user management perspective there are also two types of FTP regular FTP in which

files are transferred using the username and password of a regular user FTP server and

anonymous FTP in which general access is provided to the FTP server using a well known

universal login method

Active FTP

The sequence of events for active FTP is

1 Your client connects to the FTP server by establishing an FTP control connection to

port 21 of the server Your commands such as ls and get are sent over this connection

2 Whenever the client requests data over the control connection the server initiates data

transfer connections back to the client The source port of these data transfer

connections is always port 20 on the server and the destination port is a high port

(greater than 1024) on the client

3 Thus the ls listing that you asked for comes back over the port 20 to high port

connection not the port 21 control connection

FTP active mode therefore transfers data in a counter intuitive way to the TCP standard as it

selects port 20 as its source port (not a random high port thats greater than 1024) and connects

back to the client on a random high port that has been pre-negotiated on the port 21 control

connection

Active FTP may fail in cases where the client is protected from the Internet via many to one

NAT (masquerading) This is because the firewall will not know which of the many servers

behind it should receive the return connection

Passive FTP

Passive FTP works differently

1 Your client connects to the FTP server by establishing an FTP control connection to

port 21 of the server Your commands such as ls and get are sent over that connection

2 Whenever the client requests data over the control connection the client initiates the

data transfer connections to the server The source port of these data transfer

connections is always a high port on the client with a destination port of a high port on

the server

Passive FTP should be viewed as the server never making an active attempt to connect to the

client for FTP data transfers Because client always initiates the required connections passive

FTP works better for clients protected by a firewall

As Windows defaults to active FTP and Linux defaults to passive youll probably have to

accommodate both forms when deciding upon a security policy for your FTP server

Regular FTP

By default the VSFTPD package allows regular Linux users to copy files to and from their

home directories with an FTP client using their Linux usernames and passwords as their login

credentials

VSFTPD also has the option of allowing this type of access to only a group of Linux users

enabling you to restrict the addition of new files to your system to authorized personnel

The disadvantage of regular FTP is that it isnt suitable for general download distribution of

software as everyone either has to get a unique Linux user account or has to use a shared

username and password Anonymous FTP allows you to avoid this difficulty

Anonymous FTP

Anonymous FTP is the choice of Web sites that need to exchange files with numerous

unknown remote users Common uses include downloading software updates and MP3s and

uploading diagnostic information for a technical support engineers attention Unlike regular

FTP where you login with a preconfigured Linux username and password anonymous FTP

requires only a username of anonymous and your email address for the password Once logged

in to a VSFTPD server you automatically have access to only the default anonymous FTP

directory (varftp in the case of VSFTPD) and all its subdirectories

What is an FTP Site

An FTP site is like a large filing cabinet With

a traditional filing cabinet the person who does

the filing has the option to label and organize

the files how ever they see fit They also decide which files to keep locked and which remain

public It is the same with an FTP site

The virtual key to get into an FTP site is the UserID and Password If the creator of the FTP

site is willing to give everyone access to the files the UserID is anonymous and the Password

is your e-mail address (eg namedomaincom) If the FTP site is not public there will be a

unique UserID and Password for each person who is granted accessWhen connecting to an

FTP site that allows anonymous logins youre frequently not prompted for a name and

password Hence when downloading from the Internet you most likely are using an

anonymous FTP login and you dont even know itTo make an FTP connection you can use a

standard Web browser (Internet Explorer Netscape etc) or a dedicated FTP software

program referred to as an FTP ClientWhen using a Web browser for an FTP connection FTP

uploads are difficult or sometimes impossible and downloads are not protected (not

recommended for uploading or downloading large files) When connecting with an FTP

Client uploads and downloads couldnt be easier and you have added security and additional

features For one youre able to to resume a download that did not successfully finish which

is a very nice feature for people using dial-up connections who frequently loose their Internet

connection

What is an FTP Client

An FTP Client is software that is designed to transfer files back-and-forth between two

computers over the Internet It needs to be installed on your computer and can only be used

with a live connection to the Internet

The classic FTP Client look is a two-pane design The pane on the left displays the files on

your computer and the pane on the right displays the files on the remote computer

File transfers are as easy as dragging-and-dropping files from one pane to the other or by

highlighting a file and clicking one of the direction arrows located between the panes

Additional features of the FTP Client include multiple file transfer the auto re-get or resuming

feature a queuing utility the scheduling feature an FTP find utility a synchronize utility and

for the advanced user a scripting utility

All of these features will be explained in later tutorials First you need to download and install an FTP Client

Connection methods

FTP runs exclusively over TCP It defaults to listen on port 21 for incoming connections from

FTP clients A connection to this port from the FTP Client forms the control stream on which

commands are passed to the FTP server from the FTP client and on occasion from the FTP

server to the FTP client FTP uses out-of-band control which means it uses a separate

connection for control and data Thus for the actual file transfer to take place a different

connection is required which is called the data stream Depending on the transfer mode the

process of setting up the data stream is different

In active mode the FTP client opens a dynamic port sends the FTP server the dynamic port

number on which it is listening over the control stream and waits for a connection from the

FTP server When the FTP server initiates the data connection to the FTP client it binds the

source port to port 20 on the FTP server

In passive mode the FTP server opens a dynamic port sends the FTP client the servers IP

address to connect to and the port on which it is listening (a 16-bit value broken into a high and

low byte as explained above) over the control stream and waits for a connection from the FTP

client In this case the FTP client binds the source port of the connection to a dynamic port

To use passive mode the client sends the PASV command to which the server would reply

with something similar to 227 Entering Passive Mode (12700119252) The syntax of the

IP address and port are the same as for the argument to the PORT command

While data is being transferred via the data stream the control stream sits idle This can cause

problems with large data transfers through firewalls which time out sessions after lengthy

Regular FTP

By default the VSFTPD package allows regular Linux users to copy files to and from their

home directories with an FTP client using their Linux usernames and passwords as their login

credentials

VSFTPD also has the option of allowing this type of access to only a group of Linux users

enabling you to restrict the addition of new files to your system to authorized personnel

The disadvantage of regular FTP is that it isnt suitable for general download distribution of

software as everyone either has to get a unique Linux user account or has to use a shared

username and password Anonymous FTP allows you to avoid this difficulty

Anonymous FTP

Anonymous FTP is the choice of Web sites that need to exchange files with numerous

unknown remote users Common uses include downloading software updates and MP3s and

uploading diagnostic information for a technical support engineers attention Unlike regular

FTP where you login with a preconfigured Linux username and password anonymous FTP

requires only a username of anonymous and your email address for the password Once logged

in to a VSFTPD server you automatically have access to only the default anonymous FTP

directory (varftp in the case of VSFTPD) and all its subdirectories

What is an FTP Site

An FTP site is like a large filing cabinet With

a traditional filing cabinet the person who does

the filing has the option to label and organize

the files how ever they see fit They also decide which files to keep locked and which remain

public It is the same with an FTP site

The virtual key to get into an FTP site is the UserID and Password If the creator of the FTP

site is willing to give everyone access to the files the UserID is anonymous and the Password

is your e-mail address (eg namedomaincom) If the FTP site is not public there will be a

unique UserID and Password for each person who is granted accessWhen connecting to an

FTP site that allows anonymous logins youre frequently not prompted for a name and

password Hence when downloading from the Internet you most likely are using an

anonymous FTP login and you dont even know itTo make an FTP connection you can use a

standard Web browser (Internet Explorer Netscape etc) or a dedicated FTP software

program referred to as an FTP ClientWhen using a Web browser for an FTP connection FTP

uploads are difficult or sometimes impossible and downloads are not protected (not

recommended for uploading or downloading large files) When connecting with an FTP

Client uploads and downloads couldnt be easier and you have added security and additional

features For one youre able to to resume a download that did not successfully finish which

is a very nice feature for people using dial-up connections who frequently loose their Internet

connection

What is an FTP Client

An FTP Client is software that is designed to transfer files back-and-forth between two

computers over the Internet It needs to be installed on your computer and can only be used

with a live connection to the Internet

The classic FTP Client look is a two-pane design The pane on the left displays the files on

your computer and the pane on the right displays the files on the remote computer

File transfers are as easy as dragging-and-dropping files from one pane to the other or by

highlighting a file and clicking one of the direction arrows located between the panes

Additional features of the FTP Client include multiple file transfer the auto re-get or resuming

feature a queuing utility the scheduling feature an FTP find utility a synchronize utility and

for the advanced user a scripting utility

All of these features will be explained in later tutorials First you need to download and install an FTP Client

Connection methods

FTP runs exclusively over TCP It defaults to listen on port 21 for incoming connections from

FTP clients A connection to this port from the FTP Client forms the control stream on which

commands are passed to the FTP server from the FTP client and on occasion from the FTP

server to the FTP client FTP uses out-of-band control which means it uses a separate

connection for control and data Thus for the actual file transfer to take place a different

connection is required which is called the data stream Depending on the transfer mode the

process of setting up the data stream is different

In active mode the FTP client opens a dynamic port sends the FTP server the dynamic port

number on which it is listening over the control stream and waits for a connection from the

FTP server When the FTP server initiates the data connection to the FTP client it binds the

source port to port 20 on the FTP server

In passive mode the FTP server opens a dynamic port sends the FTP client the servers IP

address to connect to and the port on which it is listening (a 16-bit value broken into a high and

low byte as explained above) over the control stream and waits for a connection from the FTP

client In this case the FTP client binds the source port of the connection to a dynamic port

To use passive mode the client sends the PASV command to which the server would reply

with something similar to 227 Entering Passive Mode (12700119252) The syntax of the

IP address and port are the same as for the argument to the PORT command

While data is being transferred via the data stream the control stream sits idle This can cause

problems with large data transfers through firewalls which time out sessions after lengthy

the files how ever they see fit They also decide which files to keep locked and which remain

public It is the same with an FTP site

The virtual key to get into an FTP site is the UserID and Password If the creator of the FTP

site is willing to give everyone access to the files the UserID is anonymous and the Password

is your e-mail address (eg namedomaincom) If the FTP site is not public there will be a

unique UserID and Password for each person who is granted accessWhen connecting to an

FTP site that allows anonymous logins youre frequently not prompted for a name and

password Hence when downloading from the Internet you most likely are using an

anonymous FTP login and you dont even know itTo make an FTP connection you can use a

standard Web browser (Internet Explorer Netscape etc) or a dedicated FTP software

program referred to as an FTP ClientWhen using a Web browser for an FTP connection FTP

uploads are difficult or sometimes impossible and downloads are not protected (not

recommended for uploading or downloading large files) When connecting with an FTP

Client uploads and downloads couldnt be easier and you have added security and additional

features For one youre able to to resume a download that did not successfully finish which

is a very nice feature for people using dial-up connections who frequently loose their Internet

connection

What is an FTP Client

An FTP Client is software that is designed to transfer files back-and-forth between two

computers over the Internet It needs to be installed on your computer and can only be used

with a live connection to the Internet

The classic FTP Client look is a two-pane design The pane on the left displays the files on

your computer and the pane on the right displays the files on the remote computer

File transfers are as easy as dragging-and-dropping files from one pane to the other or by

highlighting a file and clicking one of the direction arrows located between the panes

Additional features of the FTP Client include multiple file transfer the auto re-get or resuming

feature a queuing utility the scheduling feature an FTP find utility a synchronize utility and

for the advanced user a scripting utility

All of these features will be explained in later tutorials First you need to download and install an FTP Client

Connection methods

FTP runs exclusively over TCP It defaults to listen on port 21 for incoming connections from

FTP clients A connection to this port from the FTP Client forms the control stream on which

commands are passed to the FTP server from the FTP client and on occasion from the FTP

server to the FTP client FTP uses out-of-band control which means it uses a separate

connection for control and data Thus for the actual file transfer to take place a different

connection is required which is called the data stream Depending on the transfer mode the

process of setting up the data stream is different

In active mode the FTP client opens a dynamic port sends the FTP server the dynamic port

number on which it is listening over the control stream and waits for a connection from the

FTP server When the FTP server initiates the data connection to the FTP client it binds the

source port to port 20 on the FTP server

In passive mode the FTP server opens a dynamic port sends the FTP client the servers IP

address to connect to and the port on which it is listening (a 16-bit value broken into a high and

low byte as explained above) over the control stream and waits for a connection from the FTP

client In this case the FTP client binds the source port of the connection to a dynamic port

To use passive mode the client sends the PASV command to which the server would reply

with something similar to 227 Entering Passive Mode (12700119252) The syntax of the

IP address and port are the same as for the argument to the PORT command

While data is being transferred via the data stream the control stream sits idle This can cause

problems with large data transfers through firewalls which time out sessions after lengthy

File transfers are as easy as dragging-and-dropping files from one pane to the other or by

highlighting a file and clicking one of the direction arrows located between the panes

Additional features of the FTP Client include multiple file transfer the auto re-get or resuming

feature a queuing utility the scheduling feature an FTP find utility a synchronize utility and

for the advanced user a scripting utility

All of these features will be explained in later tutorials First you need to download and install an FTP Client

Connection methods

FTP runs exclusively over TCP It defaults to listen on port 21 for incoming connections from

FTP clients A connection to this port from the FTP Client forms the control stream on which

commands are passed to the FTP server from the FTP client and on occasion from the FTP

server to the FTP client FTP uses out-of-band control which means it uses a separate

connection for control and data Thus for the actual file transfer to take place a different

connection is required which is called the data stream Depending on the transfer mode the

process of setting up the data stream is different

In active mode the FTP client opens a dynamic port sends the FTP server the dynamic port

number on which it is listening over the control stream and waits for a connection from the

FTP server When the FTP server initiates the data connection to the FTP client it binds the

source port to port 20 on the FTP server

In passive mode the FTP server opens a dynamic port sends the FTP client the servers IP

address to connect to and the port on which it is listening (a 16-bit value broken into a high and

low byte as explained above) over the control stream and waits for a connection from the FTP

client In this case the FTP client binds the source port of the connection to a dynamic port

To use passive mode the client sends the PASV command to which the server would reply

with something similar to 227 Entering Passive Mode (12700119252) The syntax of the

IP address and port are the same as for the argument to the PORT command

While data is being transferred via the data stream the control stream sits idle This can cause

problems with large data transfers through firewalls which time out sessions after lengthy

FTP runs exclusively over TCP It defaults to listen on port 21 for incoming connections from

FTP clients A connection to this port from the FTP Client forms the control stream on which

commands are passed to the FTP server from the FTP client and on occasion from the FTP

server to the FTP client FTP uses out-of-band control which means it uses a separate

connection for control and data Thus for the actual file transfer to take place a different

connection is required which is called the data stream Depending on the transfer mode the

process of setting up the data stream is different

In active mode the FTP client opens a dynamic port sends the FTP server the dynamic port

number on which it is listening over the control stream and waits for a connection from the

FTP server When the FTP server initiates the data connection to the FTP client it binds the

source port to port 20 on the FTP server

In passive mode the FTP server opens a dynamic port sends the FTP client the servers IP

address to connect to and the port on which it is listening (a 16-bit value broken into a high and

low byte as explained above) over the control stream and waits for a connection from the FTP

client In this case the FTP client binds the source port of the connection to a dynamic port

To use passive mode the client sends the PASV command to which the server would reply

with something similar to 227 Entering Passive Mode (12700119252) The syntax of the

IP address and port are the same as for the argument to the PORT command

While data is being transferred via the data stream the control stream sits idle This can cause

problems with large data transfers through firewalls which time out sessions after lengthy

periods of idleness While the file may well be successfully transferred the control session can

be disconnected by the firewall causing an error to be generated

The FTP protocol supports resuming of interrupted downloads using the REST command The

client passes the number of bytes it has already received as argument to the REST command

and restarts the transfer In some commandline clients for example there is an often-ignored

but valuable command reget (meaning get again) that will cause an interrupted get

command to be continued hopefully to completion after a communications interruption

Resuming uploads is not as easy Although the FTP protocol supports the APPE command to

append data to a file on the server the client does not know the exact position at which a

transfer got interrupted It has to obtain the size of the file some other way for example over a

directory listing or using the SIZE command

In ASCII mode (see below) resuming transfers can be troublesome if client and server use

different end of line characters

The objectives of FTP as outlined by its RFC are

1 To promote sharing of files (computer programs andor data)

2 To encourage indirect or implicit use of remote computers

3 To shield a user from variations in file storage systems among different hosts

4 To transfer data reliably and efficientl

Criticisms of FTP

Passwords and file contents are sent in clear text which can be intercepted by

eavesdroppers There are protocol enhancements that remedy this for instance by using

SSL TLS or Kerberos

Multiple TCPIP connections are used one for the control connection and one for each

download upload or directory listing Firewalls may need additional logic andor

configuration changes to account for these connections

It is hard to filter active mode FTP traffic on the client side by using a firewall since

the client must open an arbitrary port in order to receive the connection This problem

is largely resolved by using passive mode FTP

It is possible to abuse the protocols built-in proxy features to tell a server to send data

to an arbitrary port of a third computer see FXP

FTP is a high latency protocol due to the number of commands needed to initiate a

transfer

No integrity check on the receiver side If a transfer is interrupted the receiver has no

way to know if the received file is complete or not Some servers support extensions to

calculate for example a files MD5 sum (eg using the SITE MD5 command) XCRC

XMD5 XSHA or CRC checksum however even then the client has to make explicit

use of them In the absence of such extensions integrity checks have to be managed

externally

No datetimestamp attribute transfer Uploaded files are given a new current timestamp

unlike other file transfer protocols such as SFTP which allow attributes to be included

There is no way in the standard FTP protocol to set the time-last-modified (or time-

created) datestamp that most modern filesystems preserve There is a draft of a

proposed extension that adds new commands for this but as of yet most of the popular

FTP servers do not support it

Installing (Setup ) FTP Server (VSFTPD) packages

You need the vsftpd-121-5i386rpm for Red hatFedora packages for install the new FTP

server in the red hat Linux you can install the Ftp Server by using two commands as following

1 By using RPM command

2 By using YUM server

1 By using the RPM command - to install the packages write following command

rpm ndashivh vsftpd --aid ndashforce

2 By using the yum Server-to install the packages do as following

yum install vsftd

After install the ftp server VSFTPD only reads the contents of its vsftpdconf configuration

file only when it starts so youll have to restart VSFTPD each time you edit the file in order for

the changes to take effect The file may be located in either the etc or the etcvsftpd

directories depending on your Linux distribution

After Installing the Vsftps open the vsftpd file in vi editior as following

vi etcvsftpdvsftpdconf

The vsftpdconf File

Basic view of the vsftpdconf file

Allow anonymous FTPanonymous_enable=YES The directory which vsftpd will try to change into after an anonymous login (Default = varftp)anon_root=datadirectory Uncomment this to allow local users to log inlocal_enable=YES Uncomment this to enable any form of FTP write command (Needed even if you want local users to be able to upload files)write_enable=YES Uncomment to allow the anonymous FTP user to upload files This only has an effect if global write enable is activated Also you will obviously need to create a directory writable by the FTP useranon_upload_enable=YES Uncomment this if you want the anonymous FTP user to be able to create new directoriesanon_mkdir_write_enable=YES Activate logging of uploadsdownloadsxferlog_enable=YES You may override where the log file goes if you like The default is shown belowxferlog_file=varlogvsftpdlog

Defaults setting of the Vsftpd conf files

VSFTPD only reads the contents of its vsftpdconf configuration file only when it starts so

youll have to restart VSFTPD each time you edit the file in order for the changes to take

effect The file may be located in either the etc or the etcvsftpd directories depending on your

Linux distribution

This file uses a number of default settings you need to know about

VSFTPD runs as an anonymous FTP server Unless you want any remote user to log

into to your default FTP directory using a username of anonymous and a password thats the

same as their email address I would suggest turning this off The configuration files

anonymous_enable directive can be set to no to disable this feature Youll also need to

simultaneously enable local users to be able to log in by removing the comment symbol ()

before the local_enable instruction

If you enable anonymous FTP with VSFTPD remember to define the root directory

that visitors will visit This is done with the anon_root directive

anon_root=datadirectory

VSFTPD allows only anonymous FTP downloads to remote users not uploads from

them This can be changed by modifying the anon_upload_enable directive shown later

VSFTPD doesnt allow anonymous users to create directories on your FTP server You

can change this by modifying the anon_mkdir_write_enable directive

VSFTPD logs FTP access to the varlogvsftpdlog log file You can change this by

modifying the xferlog_file directive

By default VSFTPD expects files for anonymous FTP to be placed in the varftp

directory You can change this by modifying the anon_root directive There is always the risk

with anonymous FTP that users will discover a way to write files to your anonymous FTP

directory You run the risk of filling up your var partition if you use the default setting It is

best to make the anonymous FTP directory reside in its own dedicated partition

Yum server

About Yum server

It is the server in which we place all the pacakages of the linux which we wants to install on

the client computer as well as on server computer(Yum server) as show in the figure

Before installing the yum server we use the RPM command to install the

pacakages which is difficult to install and use because we can not install all the packages in

one time we run rpm command individual for installing the all depend ices of the packages

in the rpm command we need the cd and dvd of the pacakages to install on evey time to install

but in the yum server we copy the cd in the system not need to cd or dvd of the pacakage on

every time to install After installing the yum server we not need to install the all dependences

of the packages just write the following command and your pacakages will install

yum install pacakages name

Installation (setup) of the yum server

Method for installing the yum Server

1 Copy all Rpm Packages from the DVD of linux in the system on directory

2 Install the vsftpd and createrepo packages in the linux

3 Create the data base of all packages

4 Then create repo file of the yum server

5 Start the yum server

To install the yum server first of all copy all the pancakes of Linux in one directory for

example we copy all the packages in the Server directory

1 Insert the DVD of the red hat Linux in cd rom

2 Mount the cdRom in media directory using following command

mount devcdrom media

cd media

cd Serve

3 After opening the server directory then copy all the packages from the server

directory in the computer directory varftppub by using following command

cp ndashvar mediaServer varftppub

Installing vsftpd and createrepo packages in the linux

Before installing the yum server we install the vsftpd packages in the system to configure the

ftp server because It is necessary to transfer the packages over the network and yum is used to

install the packages for installing these packages use following commands

After install the upper packages open the location of the where we copy all the packages and

create the data base of all the packages

Creating the database of the all packages by Using the following commands

createrepo -v varftppubServer

Computer take few minutes to create the database of all packages in this directory

Creating the repo files to setup the yum server

This file contain all the setting of the yum server and location of the packages where the

packages placed in the server This files is created by two type as following

1 On server Computer

2 On client Computer

1 On the server side - on the server open the following director and make the repo

file by using the vi editor as following

In this file write following things

name - itrsquos the server name you can write any name on that as that name

baseurl- it is the location of all the packages where they palaced in the computer

system

enabled - if it is one the yum server is start if it is 0 then it is disabled

After making the above file save the file and start the yum server and refresh th server

by using following command

After this start the service of ftp and yum as following

yum clean all

service vsftpd restart

chkconfig vsftpd

Now the yum server is ready to use

Yum server setting on the client computer

On client computer create the following file by using the vi editior

vi etcyumreposdpreetrepo

In this file write the following things

[class]

name=harry

baseurl=ftp192168050pubserver

enabled=1

gpgcheck=0

then save the file and exit

name - itrsquos the server name you can write any name on that as that name

baseurl- it is the location(ftp location) of all the packages where they placed in the server

computer system

enabled - if it is one the yum server is start if it is 0 then it is disabled

start the service by using the following

yum clean all

Apache HTTP Server

APACHE LOGO

The Apache HTTP Server is web server software notable for playing a key role in the initial growth of the World Wide Web Released under the Apache License Apache is characterized as open source software

Features

Apache supports a variety of features many implemented as compiled modules which extend the core functionality These can range from server-side programming language support to authentication schemes Some common language interfaces support Perl Python Tcl and PHP Popular authentication modules include mod_access mod_auth mod_digest and mod_auth_digest the successor to mod_digest A sample of other features include SSL and TLS support (mod_ssl) a proxy module (mod_proxy) a URL rewriter (also known as a rewrite engine implemented under mod_rewrite) custom log files (mod_log_config) and filtering support (mod_include and mod_ext_filter)

Virtual hosting allows one Apache installation to serve many different actual websites For example one machine with one Apache installation could simultaneously serve wwwexamplecom wwwtestcom test47test-servertestcom etc

Apache is used for many other tasks where content needs to be made available in a secure and reliable way One example is sharing files from a personal computer over the Internet A user who has Apache installed on their desktop can put arbitrary files in Apaches document root which can then be shared

The main design goal of Apache is not to be the fastest web server but rather to implement almost all the standards

The default configuration file installed with the Apache HTTP Server works without alteration for most situations This chapter outlines many of the directives found within its configuration file (etchttpdconfhttpdconf) to aid those who require a custom configuration

Features of Apache HTTP Server 20

The arrival of Apache HTTP Server 20 brings with it a number of new features including

New Apache API mdash Modules utilize a new more powerful set of Application Programming Interfaces (APIs) Filtering mdash Modules can act as content filters

The vsftpdconf File

Basic view of the vsftpdconf file

Allow anonymous FTPanonymous_enable=YES The directory which vsftpd will try to change into after an anonymous login (Default = varftp)anon_root=datadirectory Uncomment this to allow local users to log inlocal_enable=YES Uncomment this to enable any form of FTP write command (Needed even if you want local users to be able to upload files)write_enable=YES Uncomment to allow the anonymous FTP user to upload files This only has an effect if global write enable is activated Also you will obviously need to create a directory writable by the FTP useranon_upload_enable=YES Uncomment this if you want the anonymous FTP user to be able to create new directoriesanon_mkdir_write_enable=YES Activate logging of uploadsdownloadsxferlog_enable=YES You may override where the log file goes if you like The default is shown belowxferlog_file=varlogvsftpdlog

Defaults setting of the Vsftpd conf files

VSFTPD only reads the contents of its vsftpdconf configuration file only when it starts so

youll have to restart VSFTPD each time you edit the file in order for the changes to take

effect The file may be located in either the etc or the etcvsftpd directories depending on your

Linux distribution

This file uses a number of default settings you need to know about

VSFTPD runs as an anonymous FTP server Unless you want any remote user to log

into to your default FTP directory using a username of anonymous and a password thats the

same as their email address I would suggest turning this off The configuration files

anonymous_enable directive can be set to no to disable this feature Youll also need to

simultaneously enable local users to be able to log in by removing the comment symbol ()

before the local_enable instruction

If you enable anonymous FTP with VSFTPD remember to define the root directory

that visitors will visit This is done with the anon_root directive

anon_root=datadirectory

VSFTPD allows only anonymous FTP downloads to remote users not uploads from

them This can be changed by modifying the anon_upload_enable directive shown later

VSFTPD doesnt allow anonymous users to create directories on your FTP server You

can change this by modifying the anon_mkdir_write_enable directive

VSFTPD logs FTP access to the varlogvsftpdlog log file You can change this by

modifying the xferlog_file directive

By default VSFTPD expects files for anonymous FTP to be placed in the varftp

directory You can change this by modifying the anon_root directive There is always the risk

with anonymous FTP that users will discover a way to write files to your anonymous FTP

directory You run the risk of filling up your var partition if you use the default setting It is

best to make the anonymous FTP directory reside in its own dedicated partition

Yum server

About Yum server

It is the server in which we place all the pacakages of the linux which we wants to install on

the client computer as well as on server computer(Yum server) as show in the figure

Before installing the yum server we use the RPM command to install the

pacakages which is difficult to install and use because we can not install all the packages in

one time we run rpm command individual for installing the all depend ices of the packages

in the rpm command we need the cd and dvd of the pacakages to install on evey time to install

but in the yum server we copy the cd in the system not need to cd or dvd of the pacakage on

every time to install After installing the yum server we not need to install the all dependences

of the packages just write the following command and your pacakages will install

yum install pacakages name

Installation (setup) of the yum server

Method for installing the yum Server

1 Copy all Rpm Packages from the DVD of linux in the system on directory

2 Install the vsftpd and createrepo packages in the linux

3 Create the data base of all packages

4 Then create repo file of the yum server

5 Start the yum server

To install the yum server first of all copy all the pancakes of Linux in one directory for

example we copy all the packages in the Server directory

1 Insert the DVD of the red hat Linux in cd rom

2 Mount the cdRom in media directory using following command

mount devcdrom media

cd media

cd Serve

3 After opening the server directory then copy all the packages from the server

directory in the computer directory varftppub by using following command

cp ndashvar mediaServer varftppub

Installing vsftpd and createrepo packages in the linux

Before installing the yum server we install the vsftpd packages in the system to configure the

ftp server because It is necessary to transfer the packages over the network and yum is used to

install the packages for installing these packages use following commands

After install the upper packages open the location of the where we copy all the packages and

create the data base of all the packages

Creating the database of the all packages by Using the following commands

createrepo -v varftppubServer

Computer take few minutes to create the database of all packages in this directory

Creating the repo files to setup the yum server

This file contain all the setting of the yum server and location of the packages where the

packages placed in the server This files is created by two type as following

1 On server Computer

2 On client Computer

1 On the server side - on the server open the following director and make the repo

file by using the vi editor as following

In this file write following things

name - itrsquos the server name you can write any name on that as that name

baseurl- it is the location of all the packages where they palaced in the computer

system

enabled - if it is one the yum server is start if it is 0 then it is disabled

After making the above file save the file and start the yum server and refresh th server

by using following command

After this start the service of ftp and yum as following

yum clean all

service vsftpd restart

chkconfig vsftpd

Now the yum server is ready to use

Yum server setting on the client computer

On client computer create the following file by using the vi editior

vi etcyumreposdpreetrepo

In this file write the following things

[class]

name=harry

baseurl=ftp192168050pubserver

enabled=1

gpgcheck=0

then save the file and exit

name - itrsquos the server name you can write any name on that as that name

baseurl- it is the location(ftp location) of all the packages where they placed in the server

computer system

enabled - if it is one the yum server is start if it is 0 then it is disabled

start the service by using the following

yum clean all

Apache HTTP Server

APACHE LOGO

The Apache HTTP Server is web server software notable for playing a key role in the initial growth of the World Wide Web Released under the Apache License Apache is characterized as open source software

Features

Apache supports a variety of features many implemented as compiled modules which extend the core functionality These can range from server-side programming language support to authentication schemes Some common language interfaces support Perl Python Tcl and PHP Popular authentication modules include mod_access mod_auth mod_digest and mod_auth_digest the successor to mod_digest A sample of other features include SSL and TLS support (mod_ssl) a proxy module (mod_proxy) a URL rewriter (also known as a rewrite engine implemented under mod_rewrite) custom log files (mod_log_config) and filtering support (mod_include and mod_ext_filter)

Virtual hosting allows one Apache installation to serve many different actual websites For example one machine with one Apache installation could simultaneously serve wwwexamplecom wwwtestcom test47test-servertestcom etc

Apache is used for many other tasks where content needs to be made available in a secure and reliable way One example is sharing files from a personal computer over the Internet A user who has Apache installed on their desktop can put arbitrary files in Apaches document root which can then be shared

The main design goal of Apache is not to be the fastest web server but rather to implement almost all the standards

The default configuration file installed with the Apache HTTP Server works without alteration for most situations This chapter outlines many of the directives found within its configuration file (etchttpdconfhttpdconf) to aid those who require a custom configuration

Features of Apache HTTP Server 20

The arrival of Apache HTTP Server 20 brings with it a number of new features including

New Apache API mdash Modules utilize a new more powerful set of Application Programming Interfaces (APIs) Filtering mdash Modules can act as content filters

Defaults setting of the Vsftpd conf files

VSFTPD only reads the contents of its vsftpdconf configuration file only when it starts so

youll have to restart VSFTPD each time you edit the file in order for the changes to take

effect The file may be located in either the etc or the etcvsftpd directories depending on your

Linux distribution

This file uses a number of default settings you need to know about

VSFTPD runs as an anonymous FTP server Unless you want any remote user to log

into to your default FTP directory using a username of anonymous and a password thats the

same as their email address I would suggest turning this off The configuration files

anonymous_enable directive can be set to no to disable this feature Youll also need to

simultaneously enable local users to be able to log in by removing the comment symbol ()

before the local_enable instruction

If you enable anonymous FTP with VSFTPD remember to define the root directory

that visitors will visit This is done with the anon_root directive

anon_root=datadirectory

VSFTPD allows only anonymous FTP downloads to remote users not uploads from

them This can be changed by modifying the anon_upload_enable directive shown later

VSFTPD doesnt allow anonymous users to create directories on your FTP server You

can change this by modifying the anon_mkdir_write_enable directive

VSFTPD logs FTP access to the varlogvsftpdlog log file You can change this by

modifying the xferlog_file directive

By default VSFTPD expects files for anonymous FTP to be placed in the varftp

directory You can change this by modifying the anon_root directive There is always the risk

with anonymous FTP that users will discover a way to write files to your anonymous FTP

directory You run the risk of filling up your var partition if you use the default setting It is

best to make the anonymous FTP directory reside in its own dedicated partition

Yum server

About Yum server

It is the server in which we place all the pacakages of the linux which we wants to install on

the client computer as well as on server computer(Yum server) as show in the figure

Before installing the yum server we use the RPM command to install the

pacakages which is difficult to install and use because we can not install all the packages in

one time we run rpm command individual for installing the all depend ices of the packages

in the rpm command we need the cd and dvd of the pacakages to install on evey time to install

but in the yum server we copy the cd in the system not need to cd or dvd of the pacakage on

every time to install After installing the yum server we not need to install the all dependences

of the packages just write the following command and your pacakages will install

yum install pacakages name

Installation (setup) of the yum server

Method for installing the yum Server

1 Copy all Rpm Packages from the DVD of linux in the system on directory

2 Install the vsftpd and createrepo packages in the linux

3 Create the data base of all packages

4 Then create repo file of the yum server

5 Start the yum server

To install the yum server first of all copy all the pancakes of Linux in one directory for

example we copy all the packages in the Server directory

1 Insert the DVD of the red hat Linux in cd rom

2 Mount the cdRom in media directory using following command

mount devcdrom media

cd media

cd Serve

3 After opening the server directory then copy all the packages from the server

directory in the computer directory varftppub by using following command

cp ndashvar mediaServer varftppub

Installing vsftpd and createrepo packages in the linux

Before installing the yum server we install the vsftpd packages in the system to configure the

ftp server because It is necessary to transfer the packages over the network and yum is used to

install the packages for installing these packages use following commands

After install the upper packages open the location of the where we copy all the packages and

create the data base of all the packages

Creating the database of the all packages by Using the following commands

createrepo -v varftppubServer

Computer take few minutes to create the database of all packages in this directory

Creating the repo files to setup the yum server

This file contain all the setting of the yum server and location of the packages where the

packages placed in the server This files is created by two type as following

1 On server Computer

2 On client Computer

1 On the server side - on the server open the following director and make the repo

file by using the vi editor as following

In this file write following things

name - itrsquos the server name you can write any name on that as that name

baseurl- it is the location of all the packages where they palaced in the computer

system

enabled - if it is one the yum server is start if it is 0 then it is disabled

After making the above file save the file and start the yum server and refresh th server

by using following command

After this start the service of ftp and yum as following

yum clean all

service vsftpd restart

chkconfig vsftpd

Now the yum server is ready to use

Yum server setting on the client computer

On client computer create the following file by using the vi editior

vi etcyumreposdpreetrepo

In this file write the following things

[class]

name=harry

baseurl=ftp192168050pubserver

enabled=1

gpgcheck=0

then save the file and exit

name - itrsquos the server name you can write any name on that as that name

baseurl- it is the location(ftp location) of all the packages where they placed in the server

computer system

enabled - if it is one the yum server is start if it is 0 then it is disabled

start the service by using the following

yum clean all

Apache HTTP Server

APACHE LOGO

The Apache HTTP Server is web server software notable for playing a key role in the initial growth of the World Wide Web Released under the Apache License Apache is characterized as open source software

Features

Apache supports a variety of features many implemented as compiled modules which extend the core functionality These can range from server-side programming language support to authentication schemes Some common language interfaces support Perl Python Tcl and PHP Popular authentication modules include mod_access mod_auth mod_digest and mod_auth_digest the successor to mod_digest A sample of other features include SSL and TLS support (mod_ssl) a proxy module (mod_proxy) a URL rewriter (also known as a rewrite engine implemented under mod_rewrite) custom log files (mod_log_config) and filtering support (mod_include and mod_ext_filter)

Virtual hosting allows one Apache installation to serve many different actual websites For example one machine with one Apache installation could simultaneously serve wwwexamplecom wwwtestcom test47test-servertestcom etc

Apache is used for many other tasks where content needs to be made available in a secure and reliable way One example is sharing files from a personal computer over the Internet A user who has Apache installed on their desktop can put arbitrary files in Apaches document root which can then be shared

The main design goal of Apache is not to be the fastest web server but rather to implement almost all the standards

The default configuration file installed with the Apache HTTP Server works without alteration for most situations This chapter outlines many of the directives found within its configuration file (etchttpdconfhttpdconf) to aid those who require a custom configuration

Features of Apache HTTP Server 20

The arrival of Apache HTTP Server 20 brings with it a number of new features including

New Apache API mdash Modules utilize a new more powerful set of Application Programming Interfaces (APIs) Filtering mdash Modules can act as content filters

Yum server

About Yum server

It is the server in which we place all the pacakages of the linux which we wants to install on

the client computer as well as on server computer(Yum server) as show in the figure

Before installing the yum server we use the RPM command to install the

pacakages which is difficult to install and use because we can not install all the packages in

one time we run rpm command individual for installing the all depend ices of the packages

in the rpm command we need the cd and dvd of the pacakages to install on evey time to install

but in the yum server we copy the cd in the system not need to cd or dvd of the pacakage on

every time to install After installing the yum server we not need to install the all dependences

of the packages just write the following command and your pacakages will install

yum install pacakages name

Installation (setup) of the yum server

Method for installing the yum Server

1 Copy all Rpm Packages from the DVD of linux in the system on directory

2 Install the vsftpd and createrepo packages in the linux

3 Create the data base of all packages

4 Then create repo file of the yum server

5 Start the yum server

To install the yum server first of all copy all the pancakes of Linux in one directory for

example we copy all the packages in the Server directory

1 Insert the DVD of the red hat Linux in cd rom

2 Mount the cdRom in media directory using following command

mount devcdrom media

cd media

cd Serve

3 After opening the server directory then copy all the packages from the server

directory in the computer directory varftppub by using following command

cp ndashvar mediaServer varftppub

Installing vsftpd and createrepo packages in the linux

Before installing the yum server we install the vsftpd packages in the system to configure the

ftp server because It is necessary to transfer the packages over the network and yum is used to

install the packages for installing these packages use following commands

After install the upper packages open the location of the where we copy all the packages and

create the data base of all the packages

Creating the database of the all packages by Using the following commands

createrepo -v varftppubServer

Computer take few minutes to create the database of all packages in this directory

Creating the repo files to setup the yum server

This file contain all the setting of the yum server and location of the packages where the

packages placed in the server This files is created by two type as following

1 On server Computer

2 On client Computer

1 On the server side - on the server open the following director and make the repo

file by using the vi editor as following

In this file write following things

name - itrsquos the server name you can write any name on that as that name

baseurl- it is the location of all the packages where they palaced in the computer

system

enabled - if it is one the yum server is start if it is 0 then it is disabled

After making the above file save the file and start the yum server and refresh th server

by using following command

After this start the service of ftp and yum as following

yum clean all

service vsftpd restart

chkconfig vsftpd

Now the yum server is ready to use

Yum server setting on the client computer

On client computer create the following file by using the vi editior

vi etcyumreposdpreetrepo

In this file write the following things

[class]

name=harry

baseurl=ftp192168050pubserver

enabled=1

gpgcheck=0

then save the file and exit

name - itrsquos the server name you can write any name on that as that name

baseurl- it is the location(ftp location) of all the packages where they placed in the server

computer system

enabled - if it is one the yum server is start if it is 0 then it is disabled

start the service by using the following

yum clean all

Apache HTTP Server

APACHE LOGO

The Apache HTTP Server is web server software notable for playing a key role in the initial growth of the World Wide Web Released under the Apache License Apache is characterized as open source software

Features

Apache supports a variety of features many implemented as compiled modules which extend the core functionality These can range from server-side programming language support to authentication schemes Some common language interfaces support Perl Python Tcl and PHP Popular authentication modules include mod_access mod_auth mod_digest and mod_auth_digest the successor to mod_digest A sample of other features include SSL and TLS support (mod_ssl) a proxy module (mod_proxy) a URL rewriter (also known as a rewrite engine implemented under mod_rewrite) custom log files (mod_log_config) and filtering support (mod_include and mod_ext_filter)

Virtual hosting allows one Apache installation to serve many different actual websites For example one machine with one Apache installation could simultaneously serve wwwexamplecom wwwtestcom test47test-servertestcom etc

Apache is used for many other tasks where content needs to be made available in a secure and reliable way One example is sharing files from a personal computer over the Internet A user who has Apache installed on their desktop can put arbitrary files in Apaches document root which can then be shared

The main design goal of Apache is not to be the fastest web server but rather to implement almost all the standards

The default configuration file installed with the Apache HTTP Server works without alteration for most situations This chapter outlines many of the directives found within its configuration file (etchttpdconfhttpdconf) to aid those who require a custom configuration

Features of Apache HTTP Server 20

The arrival of Apache HTTP Server 20 brings with it a number of new features including

New Apache API mdash Modules utilize a new more powerful set of Application Programming Interfaces (APIs) Filtering mdash Modules can act as content filters

Installation (setup) of the yum server

Method for installing the yum Server

1 Copy all Rpm Packages from the DVD of linux in the system on directory

2 Install the vsftpd and createrepo packages in the linux

3 Create the data base of all packages

4 Then create repo file of the yum server

5 Start the yum server

To install the yum server first of all copy all the pancakes of Linux in one directory for

example we copy all the packages in the Server directory

1 Insert the DVD of the red hat Linux in cd rom

2 Mount the cdRom in media directory using following command

mount devcdrom media

cd media

cd Serve

3 After opening the server directory then copy all the packages from the server

directory in the computer directory varftppub by using following command

cp ndashvar mediaServer varftppub

Installing vsftpd and createrepo packages in the linux

Before installing the yum server we install the vsftpd packages in the system to configure the

ftp server because It is necessary to transfer the packages over the network and yum is used to

install the packages for installing these packages use following commands

After install the upper packages open the location of the where we copy all the packages and

create the data base of all the packages

Creating the database of the all packages by Using the following commands

createrepo -v varftppubServer

Computer take few minutes to create the database of all packages in this directory

Creating the repo files to setup the yum server

This file contain all the setting of the yum server and location of the packages where the

packages placed in the server This files is created by two type as following

1 On server Computer

2 On client Computer

1 On the server side - on the server open the following director and make the repo

file by using the vi editor as following

In this file write following things

name - itrsquos the server name you can write any name on that as that name

baseurl- it is the location of all the packages where they palaced in the computer

system

enabled - if it is one the yum server is start if it is 0 then it is disabled

After making the above file save the file and start the yum server and refresh th server

by using following command

After this start the service of ftp and yum as following

yum clean all

service vsftpd restart

chkconfig vsftpd

Now the yum server is ready to use

Yum server setting on the client computer

On client computer create the following file by using the vi editior

vi etcyumreposdpreetrepo

In this file write the following things

[class]

name=harry

baseurl=ftp192168050pubserver

enabled=1

gpgcheck=0

then save the file and exit

name - itrsquos the server name you can write any name on that as that name

baseurl- it is the location(ftp location) of all the packages where they placed in the server

computer system

enabled - if it is one the yum server is start if it is 0 then it is disabled

start the service by using the following

yum clean all

Apache HTTP Server

APACHE LOGO

The Apache HTTP Server is web server software notable for playing a key role in the initial growth of the World Wide Web Released under the Apache License Apache is characterized as open source software

Features

Apache supports a variety of features many implemented as compiled modules which extend the core functionality These can range from server-side programming language support to authentication schemes Some common language interfaces support Perl Python Tcl and PHP Popular authentication modules include mod_access mod_auth mod_digest and mod_auth_digest the successor to mod_digest A sample of other features include SSL and TLS support (mod_ssl) a proxy module (mod_proxy) a URL rewriter (also known as a rewrite engine implemented under mod_rewrite) custom log files (mod_log_config) and filtering support (mod_include and mod_ext_filter)

Virtual hosting allows one Apache installation to serve many different actual websites For example one machine with one Apache installation could simultaneously serve wwwexamplecom wwwtestcom test47test-servertestcom etc

Apache is used for many other tasks where content needs to be made available in a secure and reliable way One example is sharing files from a personal computer over the Internet A user who has Apache installed on their desktop can put arbitrary files in Apaches document root which can then be shared

The main design goal of Apache is not to be the fastest web server but rather to implement almost all the standards

The default configuration file installed with the Apache HTTP Server works without alteration for most situations This chapter outlines many of the directives found within its configuration file (etchttpdconfhttpdconf) to aid those who require a custom configuration

Features of Apache HTTP Server 20

The arrival of Apache HTTP Server 20 brings with it a number of new features including

New Apache API mdash Modules utilize a new more powerful set of Application Programming Interfaces (APIs) Filtering mdash Modules can act as content filters

Installing vsftpd and createrepo packages in the linux

Before installing the yum server we install the vsftpd packages in the system to configure the

ftp server because It is necessary to transfer the packages over the network and yum is used to

install the packages for installing these packages use following commands

After install the upper packages open the location of the where we copy all the packages and

create the data base of all the packages

Creating the database of the all packages by Using the following commands

createrepo -v varftppubServer

Computer take few minutes to create the database of all packages in this directory

Creating the repo files to setup the yum server

This file contain all the setting of the yum server and location of the packages where the

packages placed in the server This files is created by two type as following

1 On server Computer

2 On client Computer

1 On the server side - on the server open the following director and make the repo

file by using the vi editor as following

In this file write following things

name - itrsquos the server name you can write any name on that as that name

baseurl- it is the location of all the packages where they palaced in the computer

system

enabled - if it is one the yum server is start if it is 0 then it is disabled

After making the above file save the file and start the yum server and refresh th server

by using following command

After this start the service of ftp and yum as following

yum clean all

service vsftpd restart

chkconfig vsftpd

Now the yum server is ready to use

Yum server setting on the client computer

On client computer create the following file by using the vi editior

vi etcyumreposdpreetrepo

In this file write the following things

[class]

name=harry

baseurl=ftp192168050pubserver

enabled=1

gpgcheck=0

then save the file and exit

name - itrsquos the server name you can write any name on that as that name

baseurl- it is the location(ftp location) of all the packages where they placed in the server

computer system

enabled - if it is one the yum server is start if it is 0 then it is disabled

start the service by using the following

yum clean all

Apache HTTP Server

APACHE LOGO

The Apache HTTP Server is web server software notable for playing a key role in the initial growth of the World Wide Web Released under the Apache License Apache is characterized as open source software

Features

Apache supports a variety of features many implemented as compiled modules which extend the core functionality These can range from server-side programming language support to authentication schemes Some common language interfaces support Perl Python Tcl and PHP Popular authentication modules include mod_access mod_auth mod_digest and mod_auth_digest the successor to mod_digest A sample of other features include SSL and TLS support (mod_ssl) a proxy module (mod_proxy) a URL rewriter (also known as a rewrite engine implemented under mod_rewrite) custom log files (mod_log_config) and filtering support (mod_include and mod_ext_filter)

Virtual hosting allows one Apache installation to serve many different actual websites For example one machine with one Apache installation could simultaneously serve wwwexamplecom wwwtestcom test47test-servertestcom etc

Apache is used for many other tasks where content needs to be made available in a secure and reliable way One example is sharing files from a personal computer over the Internet A user who has Apache installed on their desktop can put arbitrary files in Apaches document root which can then be shared

The main design goal of Apache is not to be the fastest web server but rather to implement almost all the standards

The default configuration file installed with the Apache HTTP Server works without alteration for most situations This chapter outlines many of the directives found within its configuration file (etchttpdconfhttpdconf) to aid those who require a custom configuration

Features of Apache HTTP Server 20

The arrival of Apache HTTP Server 20 brings with it a number of new features including

New Apache API mdash Modules utilize a new more powerful set of Application Programming Interfaces (APIs) Filtering mdash Modules can act as content filters

Creating the repo files to setup the yum server

This file contain all the setting of the yum server and location of the packages where the

packages placed in the server This files is created by two type as following

1 On server Computer

2 On client Computer

1 On the server side - on the server open the following director and make the repo

file by using the vi editor as following

In this file write following things

name - itrsquos the server name you can write any name on that as that name

baseurl- it is the location of all the packages where they palaced in the computer

system

enabled - if it is one the yum server is start if it is 0 then it is disabled

After making the above file save the file and start the yum server and refresh th server

by using following command

After this start the service of ftp and yum as following

yum clean all

service vsftpd restart

chkconfig vsftpd

Now the yum server is ready to use

Yum server setting on the client computer

On client computer create the following file by using the vi editior

vi etcyumreposdpreetrepo

In this file write the following things

[class]

name=harry

baseurl=ftp192168050pubserver

enabled=1

gpgcheck=0

then save the file and exit

name - itrsquos the server name you can write any name on that as that name

baseurl- it is the location(ftp location) of all the packages where they placed in the server

computer system

enabled - if it is one the yum server is start if it is 0 then it is disabled

start the service by using the following

yum clean all

Apache HTTP Server

APACHE LOGO

The Apache HTTP Server is web server software notable for playing a key role in the initial growth of the World Wide Web Released under the Apache License Apache is characterized as open source software

Features

Apache supports a variety of features many implemented as compiled modules which extend the core functionality These can range from server-side programming language support to authentication schemes Some common language interfaces support Perl Python Tcl and PHP Popular authentication modules include mod_access mod_auth mod_digest and mod_auth_digest the successor to mod_digest A sample of other features include SSL and TLS support (mod_ssl) a proxy module (mod_proxy) a URL rewriter (also known as a rewrite engine implemented under mod_rewrite) custom log files (mod_log_config) and filtering support (mod_include and mod_ext_filter)

Virtual hosting allows one Apache installation to serve many different actual websites For example one machine with one Apache installation could simultaneously serve wwwexamplecom wwwtestcom test47test-servertestcom etc

Apache is used for many other tasks where content needs to be made available in a secure and reliable way One example is sharing files from a personal computer over the Internet A user who has Apache installed on their desktop can put arbitrary files in Apaches document root which can then be shared

The main design goal of Apache is not to be the fastest web server but rather to implement almost all the standards

The default configuration file installed with the Apache HTTP Server works without alteration for most situations This chapter outlines many of the directives found within its configuration file (etchttpdconfhttpdconf) to aid those who require a custom configuration

Features of Apache HTTP Server 20

The arrival of Apache HTTP Server 20 brings with it a number of new features including

New Apache API mdash Modules utilize a new more powerful set of Application Programming Interfaces (APIs) Filtering mdash Modules can act as content filters

After making the above file save the file and start the yum server and refresh th server

by using following command

After this start the service of ftp and yum as following

yum clean all

service vsftpd restart

chkconfig vsftpd

Now the yum server is ready to use

Yum server setting on the client computer

On client computer create the following file by using the vi editior

vi etcyumreposdpreetrepo

In this file write the following things

[class]

name=harry

baseurl=ftp192168050pubserver

enabled=1

gpgcheck=0

then save the file and exit

name - itrsquos the server name you can write any name on that as that name

baseurl- it is the location(ftp location) of all the packages where they placed in the server

computer system

enabled - if it is one the yum server is start if it is 0 then it is disabled

start the service by using the following

yum clean all

Apache HTTP Server

APACHE LOGO

The Apache HTTP Server is web server software notable for playing a key role in the initial growth of the World Wide Web Released under the Apache License Apache is characterized as open source software

Features

Apache supports a variety of features many implemented as compiled modules which extend the core functionality These can range from server-side programming language support to authentication schemes Some common language interfaces support Perl Python Tcl and PHP Popular authentication modules include mod_access mod_auth mod_digest and mod_auth_digest the successor to mod_digest A sample of other features include SSL and TLS support (mod_ssl) a proxy module (mod_proxy) a URL rewriter (also known as a rewrite engine implemented under mod_rewrite) custom log files (mod_log_config) and filtering support (mod_include and mod_ext_filter)

Virtual hosting allows one Apache installation to serve many different actual websites For example one machine with one Apache installation could simultaneously serve wwwexamplecom wwwtestcom test47test-servertestcom etc

Apache is used for many other tasks where content needs to be made available in a secure and reliable way One example is sharing files from a personal computer over the Internet A user who has Apache installed on their desktop can put arbitrary files in Apaches document root which can then be shared

The main design goal of Apache is not to be the fastest web server but rather to implement almost all the standards

The default configuration file installed with the Apache HTTP Server works without alteration for most situations This chapter outlines many of the directives found within its configuration file (etchttpdconfhttpdconf) to aid those who require a custom configuration

Features of Apache HTTP Server 20

The arrival of Apache HTTP Server 20 brings with it a number of new features including

New Apache API mdash Modules utilize a new more powerful set of Application Programming Interfaces (APIs) Filtering mdash Modules can act as content filters

Yum server setting on the client computer

On client computer create the following file by using the vi editior

vi etcyumreposdpreetrepo

In this file write the following things

[class]

name=harry

baseurl=ftp192168050pubserver

enabled=1

gpgcheck=0

then save the file and exit

name - itrsquos the server name you can write any name on that as that name

baseurl- it is the location(ftp location) of all the packages where they placed in the server

computer system

enabled - if it is one the yum server is start if it is 0 then it is disabled

start the service by using the following

yum clean all

Apache HTTP Server

APACHE LOGO

The Apache HTTP Server is web server software notable for playing a key role in the initial growth of the World Wide Web Released under the Apache License Apache is characterized as open source software

Features

Apache supports a variety of features many implemented as compiled modules which extend the core functionality These can range from server-side programming language support to authentication schemes Some common language interfaces support Perl Python Tcl and PHP Popular authentication modules include mod_access mod_auth mod_digest and mod_auth_digest the successor to mod_digest A sample of other features include SSL and TLS support (mod_ssl) a proxy module (mod_proxy) a URL rewriter (also known as a rewrite engine implemented under mod_rewrite) custom log files (mod_log_config) and filtering support (mod_include and mod_ext_filter)

Virtual hosting allows one Apache installation to serve many different actual websites For example one machine with one Apache installation could simultaneously serve wwwexamplecom wwwtestcom test47test-servertestcom etc

Apache is used for many other tasks where content needs to be made available in a secure and reliable way One example is sharing files from a personal computer over the Internet A user who has Apache installed on their desktop can put arbitrary files in Apaches document root which can then be shared

The main design goal of Apache is not to be the fastest web server but rather to implement almost all the standards

The default configuration file installed with the Apache HTTP Server works without alteration for most situations This chapter outlines many of the directives found within its configuration file (etchttpdconfhttpdconf) to aid those who require a custom configuration

Features of Apache HTTP Server 20

The arrival of Apache HTTP Server 20 brings with it a number of new features including

New Apache API mdash Modules utilize a new more powerful set of Application Programming Interfaces (APIs) Filtering mdash Modules can act as content filters

APACHE LOGO

The Apache HTTP Server is web server software notable for playing a key role in the initial growth of the World Wide Web Released under the Apache License Apache is characterized as open source software

Features

Apache supports a variety of features many implemented as compiled modules which extend the core functionality These can range from server-side programming language support to authentication schemes Some common language interfaces support Perl Python Tcl and PHP Popular authentication modules include mod_access mod_auth mod_digest and mod_auth_digest the successor to mod_digest A sample of other features include SSL and TLS support (mod_ssl) a proxy module (mod_proxy) a URL rewriter (also known as a rewrite engine implemented under mod_rewrite) custom log files (mod_log_config) and filtering support (mod_include and mod_ext_filter)

Virtual hosting allows one Apache installation to serve many different actual websites For example one machine with one Apache installation could simultaneously serve wwwexamplecom wwwtestcom test47test-servertestcom etc

Apache is used for many other tasks where content needs to be made available in a secure and reliable way One example is sharing files from a personal computer over the Internet A user who has Apache installed on their desktop can put arbitrary files in Apaches document root which can then be shared

The main design goal of Apache is not to be the fastest web server but rather to implement almost all the standards

The default configuration file installed with the Apache HTTP Server works without alteration for most situations This chapter outlines many of the directives found within its configuration file (etchttpdconfhttpdconf) to aid those who require a custom configuration

Features of Apache HTTP Server 20

The arrival of Apache HTTP Server 20 brings with it a number of new features including

New Apache API mdash Modules utilize a new more powerful set of Application Programming Interfaces (APIs) Filtering mdash Modules can act as content filters

IPv6 Support mdash The next generation IP addressing format is supported

Simplified Directives mdash A number of confusing directives have been removed while others have been simplified

Multilingual Error Responses mdash When using Server Side Include (SSI) documents customizable error response pages can be delivered in multiple languages

Multiprotocol Support mdash Multiple protocols are supported

Secure Apache

Apache HTTP Secure Server Configuration

The mod_ssl module is a security module for the Apache HTTP Server The mod_ssl module uses the tools provided by the OpenSSL Project to add a very important feature to the Apache HTTP Server mdash the ability to encrypt communications In contrast regular HTTP communications between a browser and a Web server are sent in plain text which could be intercepted and read by someone along the route between the browser and the server

The mod_ssl configuration file is located at etchttpdconfdsslconf For this file to be loaded and hence for mod_ssl to work you must have the statement Include confdconf in the etchttpdconfhttpdconf file This statement is included by default in the default Apache HTTP Server configuration file

An Overview of Security-Related PackagesTo enable the secure server you must have the following packages installed at a minimum

httpd

The httpd package contains the httpd daemon and related utilities configuration files icons Apache HTTP Server modules man pages and other files used by the Apache HTTP Server

mod_ssl

The mod_ssl package includes the mod_ssl module which provides strong cryptography for the Apache HTTP Server via the Secure Sockets Layer (SSL) and Transport Layer Security (TLS) protocols

openssl

The openssl package contains the OpenSSL toolkit The OpenSSL toolkit implements the SSL and TLS protocols and also includes a general purpose cryptography library

An Overview of Certificates and Security

Your secure server provides security using a combination of the Secure Sockets Layer (SSL) protocol and (in most cases) a digital certificate from a Certificate Authority (CA) SSL handles the encrypted communications as well as the mutual authentication between browsers and your secure server The CA-approved digital certificate provides authentication for your secure server (the CA puts its reputation behind its certification of your organizations identity) When your browser is communicating using SSL encryption the https prefix is used at the beginning of the Uniform Resource Locator (URL) in the navigation bar

The BIND DNS ServerOn most modern networks including the Internet users locate other computers by name This frees users from the daunting task of remembering the numerical network address of network resources The most effective way to configure a network to allow such name-based connections is to set up a Domain Name Service (DNS) or a nameserver which resolves hostnames on the network to numerical addresses and vice versa

This chapter reviews the nameserver included in Red Hat Enterprise Linux and the Berkeley Internet Name Domain (BIND) DNS server with an emphasis on the structure of its configuration files and how it may be administered both locally and remotely

BIND is also known as the service named in Red Hat Enterprise Linux You can manage it via the Services Configuration Tool (system-config-service)

DNS associates hostnames with their respective IP addresses so that when users want to connect to other machines on the network they can refer to them by name without having to remember IP addresses

Use of DNS also has advantages for system administrators allowing the flexibility to change the IP address for a host without affecting name-based queries to the machine Conversely administrators can shuffle which machines handle a name-based query

DNS is normally implemented using centralized servers that are authoritative for some domains and refer to other DNS servers for other domains

When a client host requests information from a nameserver it usually connects to port 53 The nameserver then attempts to resolve the name requested If the nameserver does not have an authoritative answer about the name the which host requested or does not already have the answer cached from an earlier query it queries other nameservers called root nameservers to determine which nameservers are authoritative for the name in question Then with that information it queries the authoritative nameservers to get the requested name

Nameserver ZonesIn a DNS server such as BIND all information is stored in basic data elements called resource records A resource record is usually the fully qualified domain name (FQDN) of a host Resource records are broken down into multiple sections These sections are organized into a tree-like hierarchy consisting of a main trunk primary branches secondary branches and so forth Consider the following resource record

bobsalesexamplecomWhen looking at how a resource record is resolved to find for example the IP address that relates to a particular system read the name from right to left Each level of the hierarchy is divided by a period (often called a dot ldquo rdquo) In this example therefore com defines the top-level domain for this resource record The name example is a sub-domain under com while sales is a sub-domain under example The name furthest to the left bob identifies a resource record which is part of the salesexamplecom domain

Except for the first (leftmost) part of the resource record (bob) each section is called a zone Zone defines a specific namespace A zone contains definitions of resource records which usually contain host-to-IP address mappings and IP address-to-host mappings which are called reverse records)

Zones are defined on authoritative nameservers through the use of zone files which define the resource records in that zone Zone files are stored on primary nameservers (also called master nameservers) where changes are made to the files and secondary nameservers (also called slave nameservers) which receive zone definitions from the primary nameservers Both primary and secondary nameservers are authoritative for the zone and look the same to clients Any nameserver can be a primary or secondary nameserver for multiple zones at the same time It all depends on how the nameserver is configured

Nameserver TypesThere are two nameserver configuration types

authoritative

This category includes both primary (master) and secondary (slave) servers Those servers answer only for resource records which are part of their zones

recursive

Offers resolution services but is not authoritative for any zones Answers for all resolutions are cached in memory for a fixed period of time which is specified by the retrieved RR

BIND as a NameserverBIND is set of DNS related programs It contains a monolithic nameserver called usrsbinnamed an administration utility called usrsbinrndc and DNS debugging utility called usrbindig

BIND stores its configuration files in the following locations

etcnamedconf

The configuration file for the named daemon

varnamed directory

The named working directory which stores zone and statistic files

21 Installation amp configuration of Apache HTTP

Type System V-managed servicePackages httpd httpd-devel httpd-manualDaemon usrsbinhttpdScript etcinitdhttpdPorts 80tcp (http) 443tcp (https)Configuration etchttpd varwwwRelated system-config-httpd mod_ssl

The Apache HTTP server is configured here to serve the needs of making Mail Server fully functional Here we give the installation of the Apache HTTP server on station49 We configure the server using its configuration

files to cater to the needs of displaying websites on the web browser Then the process of Name Virtualization is shown in briefThe Apache HTTP server is needed to implement the GUI mailing service called SquirrelMail use of which will be shown as we proceed through the document

1)InstallationThe packages listed above are installed by YUM utility as shown below

All the packages associated with httpd will be installed using this command and there dependencies will be resolved

2)ConfigurationThe first step in the configuring httpd will definitely be coding indexhtml In our project we display 5 websites that are designed through html coding These will be shown after successful implementation of Apache HTTP server The sites are made in the following directories

station49examplecom - varwwwhtml nikeexamplecom - varwwwhtmlnike reebokexamplecom - varwwwhtmlreebok ndtvexamplecom - varwwwndtv audiexamplecom - varwwwaudi

Now we configure Name Virtualization in the apache server through the configuration file etchttpdconfhttpdconf

The line 972 of the file is edited as shown below to enable NameVirtual by giving the IP address on port number 80 which is of httpd

Entries for the above mentioned site are added by successively defining ltVirtualHostgt ltVirtualHostgt block each for each of the above mentioned sites The code is given below

The following command must be run to refresh the changes made in the configuration file to the Operating System

service httpd restart

After successful implementation of above command our server is ready to use

3)ImplementationThe following sites were accessible through the web browser firefox in our case by typing in the name of the website in the url bar For example station49examplecom gives you the following display

Similarly the displays of sites made by us are given below in the following order nikeexamplecom reebokexamplecom ndtvexamplecom audiexamplecom

nikeexamplecom reebokexamplecom

ndtvexamplecom audiexamplecom

22 Installation amp configuration of Apache Encrypted Web Server (https)Apache can provide encrypted communications using the mod_ssl Apache module To make use of encrypted communications a client must request the https protocol which uses port 443 The configuration file for mod_ssl in Red Hat Enterprise Linux is etchttpconfdsslconf

1)Installation

The https related components can be installed by using YUM utility The package name for https is mod_ssl

The packages were successfully installed

2)ConfigurationConfiguring https involves making certificate for the encryption to implement This certificate is required to be implemented in etchttpdconfdsslconf

Here we first change our native directory to etcpkitlscerts Implementing SSL requires making certificate Here we make the certificate using make command by the name of certificatecrt as shown below While making certificate we fill the certificate details These details include name of country state organization email hostname etc

After compiling the certificate the necessary changes in the configuration file are made As we know the configuration file for https is etchttpdconfdsslconf We edit this file using VI text editor

As we see here the changes are made to the only two uncommented lines in the above screenshot to notify the exact path name and the certificate name to the configuration file The file is then savedThe successive step is to move the key file generated with the certificatecrt named certificatekey to the etcpkitlsprivate directory as mentioned in the configuration file

The httpd service is then restarted to refresh the changes made in the configuration file It should be noticed that when we restart the service we are asked for the passphrase by the shell This signifies that our Apache server is now secure

3)ImplementationThe encrypted Apache HTTP server enables the web browser to display a warning while entering a protected site This is shown below

Here we use a private handmade certificate This is not recognized by the browser until we add an exception for it by clicking on the link as shown above The certificate details can be seen as below

23 Installation and configuration of Domain Name System (DNS) Name server

A name server consists of a program or computer server that implements a name-service protocol It maps a human-recognizable identifier to a system-internal often numeric identification or addressing component

The most prominent types of name servers in operation today are the name servers of the Domain Name System (DNS) one of the two principal name spaces of the Internet The most important function of these DNS servers is the translation (resolution) of humanly memorable domain names and hostnames into the corresponding numeric Internet Protocol (IP) addresses the second principal Internet name space used to identify and locate computer systems and resources on the Internet

Configuration Files

varnamedchrootetcnamedconfvarnamedchrootvarnamedfzonevarnamedchrootvarnamedrzone

Type System V-managedDaemon usrsbinnamed

The openssl package contains the OpenSSL toolkit The OpenSSL toolkit implements the SSL and TLS protocols and also includes a general purpose cryptography library

An Overview of Certificates and Security

Your secure server provides security using a combination of the Secure Sockets Layer (SSL) protocol and (in most cases) a digital certificate from a Certificate Authority (CA) SSL handles the encrypted communications as well as the mutual authentication between browsers and your secure server The CA-approved digital certificate provides authentication for your secure server (the CA puts its reputation behind its certification of your organizations identity) When your browser is communicating using SSL encryption the https prefix is used at the beginning of the Uniform Resource Locator (URL) in the navigation bar

The BIND DNS ServerOn most modern networks including the Internet users locate other computers by name This frees users from the daunting task of remembering the numerical network address of network resources The most effective way to configure a network to allow such name-based connections is to set up a Domain Name Service (DNS) or a nameserver which resolves hostnames on the network to numerical addresses and vice versa

This chapter reviews the nameserver included in Red Hat Enterprise Linux and the Berkeley Internet Name Domain (BIND) DNS server with an emphasis on the structure of its configuration files and how it may be administered both locally and remotely

BIND is also known as the service named in Red Hat Enterprise Linux You can manage it via the Services Configuration Tool (system-config-service)

DNS associates hostnames with their respective IP addresses so that when users want to connect to other machines on the network they can refer to them by name without having to remember IP addresses

Use of DNS also has advantages for system administrators allowing the flexibility to change the IP address for a host without affecting name-based queries to the machine Conversely administrators can shuffle which machines handle a name-based query

DNS is normally implemented using centralized servers that are authoritative for some domains and refer to other DNS servers for other domains

When a client host requests information from a nameserver it usually connects to port 53 The nameserver then attempts to resolve the name requested If the nameserver does not have an authoritative answer about the name the which host requested or does not already have the answer cached from an earlier query it queries other nameservers called root nameservers to determine which nameservers are authoritative for the name in question Then with that information it queries the authoritative nameservers to get the requested name

Nameserver ZonesIn a DNS server such as BIND all information is stored in basic data elements called resource records A resource record is usually the fully qualified domain name (FQDN) of a host Resource records are broken down into multiple sections These sections are organized into a tree-like hierarchy consisting of a main trunk primary branches secondary branches and so forth Consider the following resource record

bobsalesexamplecomWhen looking at how a resource record is resolved to find for example the IP address that relates to a particular system read the name from right to left Each level of the hierarchy is divided by a period (often called a dot ldquo rdquo) In this example therefore com defines the top-level domain for this resource record The name example is a sub-domain under com while sales is a sub-domain under example The name furthest to the left bob identifies a resource record which is part of the salesexamplecom domain

Except for the first (leftmost) part of the resource record (bob) each section is called a zone Zone defines a specific namespace A zone contains definitions of resource records which usually contain host-to-IP address mappings and IP address-to-host mappings which are called reverse records)

Zones are defined on authoritative nameservers through the use of zone files which define the resource records in that zone Zone files are stored on primary nameservers (also called master nameservers) where changes are made to the files and secondary nameservers (also called slave nameservers) which receive zone definitions from the primary nameservers Both primary and secondary nameservers are authoritative for the zone and look the same to clients Any nameserver can be a primary or secondary nameserver for multiple zones at the same time It all depends on how the nameserver is configured

Nameserver TypesThere are two nameserver configuration types

authoritative

This category includes both primary (master) and secondary (slave) servers Those servers answer only for resource records which are part of their zones

recursive

Offers resolution services but is not authoritative for any zones Answers for all resolutions are cached in memory for a fixed period of time which is specified by the retrieved RR

BIND as a NameserverBIND is set of DNS related programs It contains a monolithic nameserver called usrsbinnamed an administration utility called usrsbinrndc and DNS debugging utility called usrbindig

BIND stores its configuration files in the following locations

etcnamedconf

The configuration file for the named daemon

varnamed directory

The named working directory which stores zone and statistic files

21 Installation amp configuration of Apache HTTP

Type System V-managed servicePackages httpd httpd-devel httpd-manualDaemon usrsbinhttpdScript etcinitdhttpdPorts 80tcp (http) 443tcp (https)Configuration etchttpd varwwwRelated system-config-httpd mod_ssl

The Apache HTTP server is configured here to serve the needs of making Mail Server fully functional Here we give the installation of the Apache HTTP server on station49 We configure the server using its configuration

files to cater to the needs of displaying websites on the web browser Then the process of Name Virtualization is shown in briefThe Apache HTTP server is needed to implement the GUI mailing service called SquirrelMail use of which will be shown as we proceed through the document

1)InstallationThe packages listed above are installed by YUM utility as shown below

All the packages associated with httpd will be installed using this command and there dependencies will be resolved

2)ConfigurationThe first step in the configuring httpd will definitely be coding indexhtml In our project we display 5 websites that are designed through html coding These will be shown after successful implementation of Apache HTTP server The sites are made in the following directories

station49examplecom - varwwwhtml nikeexamplecom - varwwwhtmlnike reebokexamplecom - varwwwhtmlreebok ndtvexamplecom - varwwwndtv audiexamplecom - varwwwaudi

Now we configure Name Virtualization in the apache server through the configuration file etchttpdconfhttpdconf

The line 972 of the file is edited as shown below to enable NameVirtual by giving the IP address on port number 80 which is of httpd

Entries for the above mentioned site are added by successively defining ltVirtualHostgt ltVirtualHostgt block each for each of the above mentioned sites The code is given below

The following command must be run to refresh the changes made in the configuration file to the Operating System

service httpd restart

After successful implementation of above command our server is ready to use

3)ImplementationThe following sites were accessible through the web browser firefox in our case by typing in the name of the website in the url bar For example station49examplecom gives you the following display

Similarly the displays of sites made by us are given below in the following order nikeexamplecom reebokexamplecom ndtvexamplecom audiexamplecom

nikeexamplecom reebokexamplecom

ndtvexamplecom audiexamplecom

22 Installation amp configuration of Apache Encrypted Web Server (https)Apache can provide encrypted communications using the mod_ssl Apache module To make use of encrypted communications a client must request the https protocol which uses port 443 The configuration file for mod_ssl in Red Hat Enterprise Linux is etchttpconfdsslconf

1)Installation

The https related components can be installed by using YUM utility The package name for https is mod_ssl

The packages were successfully installed

2)ConfigurationConfiguring https involves making certificate for the encryption to implement This certificate is required to be implemented in etchttpdconfdsslconf

Here we first change our native directory to etcpkitlscerts Implementing SSL requires making certificate Here we make the certificate using make command by the name of certificatecrt as shown below While making certificate we fill the certificate details These details include name of country state organization email hostname etc

After compiling the certificate the necessary changes in the configuration file are made As we know the configuration file for https is etchttpdconfdsslconf We edit this file using VI text editor

As we see here the changes are made to the only two uncommented lines in the above screenshot to notify the exact path name and the certificate name to the configuration file The file is then savedThe successive step is to move the key file generated with the certificatecrt named certificatekey to the etcpkitlsprivate directory as mentioned in the configuration file

The httpd service is then restarted to refresh the changes made in the configuration file It should be noticed that when we restart the service we are asked for the passphrase by the shell This signifies that our Apache server is now secure

3)ImplementationThe encrypted Apache HTTP server enables the web browser to display a warning while entering a protected site This is shown below

Here we use a private handmade certificate This is not recognized by the browser until we add an exception for it by clicking on the link as shown above The certificate details can be seen as below

23 Installation and configuration of Domain Name System (DNS) Name server

A name server consists of a program or computer server that implements a name-service protocol It maps a human-recognizable identifier to a system-internal often numeric identification or addressing component

The most prominent types of name servers in operation today are the name servers of the Domain Name System (DNS) one of the two principal name spaces of the Internet The most important function of these DNS servers is the translation (resolution) of humanly memorable domain names and hostnames into the corresponding numeric Internet Protocol (IP) addresses the second principal Internet name space used to identify and locate computer systems and resources on the Internet

Configuration Files

varnamedchrootetcnamedconfvarnamedchrootvarnamedfzonevarnamedchrootvarnamedrzone

Type System V-managedDaemon usrsbinnamed

When a client host requests information from a nameserver it usually connects to port 53 The nameserver then attempts to resolve the name requested If the nameserver does not have an authoritative answer about the name the which host requested or does not already have the answer cached from an earlier query it queries other nameservers called root nameservers to determine which nameservers are authoritative for the name in question Then with that information it queries the authoritative nameservers to get the requested name

Nameserver ZonesIn a DNS server such as BIND all information is stored in basic data elements called resource records A resource record is usually the fully qualified domain name (FQDN) of a host Resource records are broken down into multiple sections These sections are organized into a tree-like hierarchy consisting of a main trunk primary branches secondary branches and so forth Consider the following resource record

bobsalesexamplecomWhen looking at how a resource record is resolved to find for example the IP address that relates to a particular system read the name from right to left Each level of the hierarchy is divided by a period (often called a dot ldquo rdquo) In this example therefore com defines the top-level domain for this resource record The name example is a sub-domain under com while sales is a sub-domain under example The name furthest to the left bob identifies a resource record which is part of the salesexamplecom domain

Except for the first (leftmost) part of the resource record (bob) each section is called a zone Zone defines a specific namespace A zone contains definitions of resource records which usually contain host-to-IP address mappings and IP address-to-host mappings which are called reverse records)

Zones are defined on authoritative nameservers through the use of zone files which define the resource records in that zone Zone files are stored on primary nameservers (also called master nameservers) where changes are made to the files and secondary nameservers (also called slave nameservers) which receive zone definitions from the primary nameservers Both primary and secondary nameservers are authoritative for the zone and look the same to clients Any nameserver can be a primary or secondary nameserver for multiple zones at the same time It all depends on how the nameserver is configured

Nameserver TypesThere are two nameserver configuration types

authoritative

This category includes both primary (master) and secondary (slave) servers Those servers answer only for resource records which are part of their zones

recursive

Offers resolution services but is not authoritative for any zones Answers for all resolutions are cached in memory for a fixed period of time which is specified by the retrieved RR

BIND as a NameserverBIND is set of DNS related programs It contains a monolithic nameserver called usrsbinnamed an administration utility called usrsbinrndc and DNS debugging utility called usrbindig

BIND stores its configuration files in the following locations

etcnamedconf

The configuration file for the named daemon

varnamed directory

The named working directory which stores zone and statistic files

21 Installation amp configuration of Apache HTTP

Type System V-managed servicePackages httpd httpd-devel httpd-manualDaemon usrsbinhttpdScript etcinitdhttpdPorts 80tcp (http) 443tcp (https)Configuration etchttpd varwwwRelated system-config-httpd mod_ssl

The Apache HTTP server is configured here to serve the needs of making Mail Server fully functional Here we give the installation of the Apache HTTP server on station49 We configure the server using its configuration

files to cater to the needs of displaying websites on the web browser Then the process of Name Virtualization is shown in briefThe Apache HTTP server is needed to implement the GUI mailing service called SquirrelMail use of which will be shown as we proceed through the document

1)InstallationThe packages listed above are installed by YUM utility as shown below

All the packages associated with httpd will be installed using this command and there dependencies will be resolved

2)ConfigurationThe first step in the configuring httpd will definitely be coding indexhtml In our project we display 5 websites that are designed through html coding These will be shown after successful implementation of Apache HTTP server The sites are made in the following directories

station49examplecom - varwwwhtml nikeexamplecom - varwwwhtmlnike reebokexamplecom - varwwwhtmlreebok ndtvexamplecom - varwwwndtv audiexamplecom - varwwwaudi

Now we configure Name Virtualization in the apache server through the configuration file etchttpdconfhttpdconf

The line 972 of the file is edited as shown below to enable NameVirtual by giving the IP address on port number 80 which is of httpd

Entries for the above mentioned site are added by successively defining ltVirtualHostgt ltVirtualHostgt block each for each of the above mentioned sites The code is given below

The following command must be run to refresh the changes made in the configuration file to the Operating System

service httpd restart

After successful implementation of above command our server is ready to use

3)ImplementationThe following sites were accessible through the web browser firefox in our case by typing in the name of the website in the url bar For example station49examplecom gives you the following display

Similarly the displays of sites made by us are given below in the following order nikeexamplecom reebokexamplecom ndtvexamplecom audiexamplecom

nikeexamplecom reebokexamplecom

ndtvexamplecom audiexamplecom

22 Installation amp configuration of Apache Encrypted Web Server (https)Apache can provide encrypted communications using the mod_ssl Apache module To make use of encrypted communications a client must request the https protocol which uses port 443 The configuration file for mod_ssl in Red Hat Enterprise Linux is etchttpconfdsslconf

1)Installation

The https related components can be installed by using YUM utility The package name for https is mod_ssl

The packages were successfully installed

2)ConfigurationConfiguring https involves making certificate for the encryption to implement This certificate is required to be implemented in etchttpdconfdsslconf

Here we first change our native directory to etcpkitlscerts Implementing SSL requires making certificate Here we make the certificate using make command by the name of certificatecrt as shown below While making certificate we fill the certificate details These details include name of country state organization email hostname etc

After compiling the certificate the necessary changes in the configuration file are made As we know the configuration file for https is etchttpdconfdsslconf We edit this file using VI text editor

As we see here the changes are made to the only two uncommented lines in the above screenshot to notify the exact path name and the certificate name to the configuration file The file is then savedThe successive step is to move the key file generated with the certificatecrt named certificatekey to the etcpkitlsprivate directory as mentioned in the configuration file

The httpd service is then restarted to refresh the changes made in the configuration file It should be noticed that when we restart the service we are asked for the passphrase by the shell This signifies that our Apache server is now secure

3)ImplementationThe encrypted Apache HTTP server enables the web browser to display a warning while entering a protected site This is shown below

Here we use a private handmade certificate This is not recognized by the browser until we add an exception for it by clicking on the link as shown above The certificate details can be seen as below

23 Installation and configuration of Domain Name System (DNS) Name server

A name server consists of a program or computer server that implements a name-service protocol It maps a human-recognizable identifier to a system-internal often numeric identification or addressing component

The most prominent types of name servers in operation today are the name servers of the Domain Name System (DNS) one of the two principal name spaces of the Internet The most important function of these DNS servers is the translation (resolution) of humanly memorable domain names and hostnames into the corresponding numeric Internet Protocol (IP) addresses the second principal Internet name space used to identify and locate computer systems and resources on the Internet

Configuration Files

varnamedchrootetcnamedconfvarnamedchrootvarnamedfzonevarnamedchrootvarnamedrzone

Type System V-managedDaemon usrsbinnamed

authoritative

This category includes both primary (master) and secondary (slave) servers Those servers answer only for resource records which are part of their zones

recursive

Offers resolution services but is not authoritative for any zones Answers for all resolutions are cached in memory for a fixed period of time which is specified by the retrieved RR

BIND as a NameserverBIND is set of DNS related programs It contains a monolithic nameserver called usrsbinnamed an administration utility called usrsbinrndc and DNS debugging utility called usrbindig

BIND stores its configuration files in the following locations

etcnamedconf

The configuration file for the named daemon

varnamed directory

The named working directory which stores zone and statistic files

21 Installation amp configuration of Apache HTTP

Type System V-managed servicePackages httpd httpd-devel httpd-manualDaemon usrsbinhttpdScript etcinitdhttpdPorts 80tcp (http) 443tcp (https)Configuration etchttpd varwwwRelated system-config-httpd mod_ssl

The Apache HTTP server is configured here to serve the needs of making Mail Server fully functional Here we give the installation of the Apache HTTP server on station49 We configure the server using its configuration

files to cater to the needs of displaying websites on the web browser Then the process of Name Virtualization is shown in briefThe Apache HTTP server is needed to implement the GUI mailing service called SquirrelMail use of which will be shown as we proceed through the document

1)InstallationThe packages listed above are installed by YUM utility as shown below

All the packages associated with httpd will be installed using this command and there dependencies will be resolved

2)ConfigurationThe first step in the configuring httpd will definitely be coding indexhtml In our project we display 5 websites that are designed through html coding These will be shown after successful implementation of Apache HTTP server The sites are made in the following directories

station49examplecom - varwwwhtml nikeexamplecom - varwwwhtmlnike reebokexamplecom - varwwwhtmlreebok ndtvexamplecom - varwwwndtv audiexamplecom - varwwwaudi

Now we configure Name Virtualization in the apache server through the configuration file etchttpdconfhttpdconf

The line 972 of the file is edited as shown below to enable NameVirtual by giving the IP address on port number 80 which is of httpd

Entries for the above mentioned site are added by successively defining ltVirtualHostgt ltVirtualHostgt block each for each of the above mentioned sites The code is given below

The following command must be run to refresh the changes made in the configuration file to the Operating System

service httpd restart

After successful implementation of above command our server is ready to use

3)ImplementationThe following sites were accessible through the web browser firefox in our case by typing in the name of the website in the url bar For example station49examplecom gives you the following display

Similarly the displays of sites made by us are given below in the following order nikeexamplecom reebokexamplecom ndtvexamplecom audiexamplecom

nikeexamplecom reebokexamplecom

ndtvexamplecom audiexamplecom

22 Installation amp configuration of Apache Encrypted Web Server (https)Apache can provide encrypted communications using the mod_ssl Apache module To make use of encrypted communications a client must request the https protocol which uses port 443 The configuration file for mod_ssl in Red Hat Enterprise Linux is etchttpconfdsslconf

1)Installation

The https related components can be installed by using YUM utility The package name for https is mod_ssl

The packages were successfully installed

2)ConfigurationConfiguring https involves making certificate for the encryption to implement This certificate is required to be implemented in etchttpdconfdsslconf

Here we first change our native directory to etcpkitlscerts Implementing SSL requires making certificate Here we make the certificate using make command by the name of certificatecrt as shown below While making certificate we fill the certificate details These details include name of country state organization email hostname etc

After compiling the certificate the necessary changes in the configuration file are made As we know the configuration file for https is etchttpdconfdsslconf We edit this file using VI text editor

As we see here the changes are made to the only two uncommented lines in the above screenshot to notify the exact path name and the certificate name to the configuration file The file is then savedThe successive step is to move the key file generated with the certificatecrt named certificatekey to the etcpkitlsprivate directory as mentioned in the configuration file

The httpd service is then restarted to refresh the changes made in the configuration file It should be noticed that when we restart the service we are asked for the passphrase by the shell This signifies that our Apache server is now secure

3)ImplementationThe encrypted Apache HTTP server enables the web browser to display a warning while entering a protected site This is shown below

Here we use a private handmade certificate This is not recognized by the browser until we add an exception for it by clicking on the link as shown above The certificate details can be seen as below

23 Installation and configuration of Domain Name System (DNS) Name server

A name server consists of a program or computer server that implements a name-service protocol It maps a human-recognizable identifier to a system-internal often numeric identification or addressing component

The most prominent types of name servers in operation today are the name servers of the Domain Name System (DNS) one of the two principal name spaces of the Internet The most important function of these DNS servers is the translation (resolution) of humanly memorable domain names and hostnames into the corresponding numeric Internet Protocol (IP) addresses the second principal Internet name space used to identify and locate computer systems and resources on the Internet

Configuration Files

varnamedchrootetcnamedconfvarnamedchrootvarnamedfzonevarnamedchrootvarnamedrzone

Type System V-managedDaemon usrsbinnamed

files to cater to the needs of displaying websites on the web browser Then the process of Name Virtualization is shown in briefThe Apache HTTP server is needed to implement the GUI mailing service called SquirrelMail use of which will be shown as we proceed through the document

1)InstallationThe packages listed above are installed by YUM utility as shown below

All the packages associated with httpd will be installed using this command and there dependencies will be resolved

2)ConfigurationThe first step in the configuring httpd will definitely be coding indexhtml In our project we display 5 websites that are designed through html coding These will be shown after successful implementation of Apache HTTP server The sites are made in the following directories

station49examplecom - varwwwhtml nikeexamplecom - varwwwhtmlnike reebokexamplecom - varwwwhtmlreebok ndtvexamplecom - varwwwndtv audiexamplecom - varwwwaudi

Now we configure Name Virtualization in the apache server through the configuration file etchttpdconfhttpdconf

The line 972 of the file is edited as shown below to enable NameVirtual by giving the IP address on port number 80 which is of httpd

Entries for the above mentioned site are added by successively defining ltVirtualHostgt ltVirtualHostgt block each for each of the above mentioned sites The code is given below

The following command must be run to refresh the changes made in the configuration file to the Operating System

service httpd restart

After successful implementation of above command our server is ready to use

3)ImplementationThe following sites were accessible through the web browser firefox in our case by typing in the name of the website in the url bar For example station49examplecom gives you the following display

Similarly the displays of sites made by us are given below in the following order nikeexamplecom reebokexamplecom ndtvexamplecom audiexamplecom

nikeexamplecom reebokexamplecom

ndtvexamplecom audiexamplecom

22 Installation amp configuration of Apache Encrypted Web Server (https)Apache can provide encrypted communications using the mod_ssl Apache module To make use of encrypted communications a client must request the https protocol which uses port 443 The configuration file for mod_ssl in Red Hat Enterprise Linux is etchttpconfdsslconf

1)Installation

The https related components can be installed by using YUM utility The package name for https is mod_ssl

The packages were successfully installed

2)ConfigurationConfiguring https involves making certificate for the encryption to implement This certificate is required to be implemented in etchttpdconfdsslconf

Here we first change our native directory to etcpkitlscerts Implementing SSL requires making certificate Here we make the certificate using make command by the name of certificatecrt as shown below While making certificate we fill the certificate details These details include name of country state organization email hostname etc

After compiling the certificate the necessary changes in the configuration file are made As we know the configuration file for https is etchttpdconfdsslconf We edit this file using VI text editor

As we see here the changes are made to the only two uncommented lines in the above screenshot to notify the exact path name and the certificate name to the configuration file The file is then savedThe successive step is to move the key file generated with the certificatecrt named certificatekey to the etcpkitlsprivate directory as mentioned in the configuration file

The httpd service is then restarted to refresh the changes made in the configuration file It should be noticed that when we restart the service we are asked for the passphrase by the shell This signifies that our Apache server is now secure

3)ImplementationThe encrypted Apache HTTP server enables the web browser to display a warning while entering a protected site This is shown below

Here we use a private handmade certificate This is not recognized by the browser until we add an exception for it by clicking on the link as shown above The certificate details can be seen as below

23 Installation and configuration of Domain Name System (DNS) Name server

A name server consists of a program or computer server that implements a name-service protocol It maps a human-recognizable identifier to a system-internal often numeric identification or addressing component

The most prominent types of name servers in operation today are the name servers of the Domain Name System (DNS) one of the two principal name spaces of the Internet The most important function of these DNS servers is the translation (resolution) of humanly memorable domain names and hostnames into the corresponding numeric Internet Protocol (IP) addresses the second principal Internet name space used to identify and locate computer systems and resources on the Internet

Configuration Files

varnamedchrootetcnamedconfvarnamedchrootvarnamedfzonevarnamedchrootvarnamedrzone

Type System V-managedDaemon usrsbinnamed

station49examplecom - varwwwhtml nikeexamplecom - varwwwhtmlnike reebokexamplecom - varwwwhtmlreebok ndtvexamplecom - varwwwndtv audiexamplecom - varwwwaudi

Now we configure Name Virtualization in the apache server through the configuration file etchttpdconfhttpdconf

The line 972 of the file is edited as shown below to enable NameVirtual by giving the IP address on port number 80 which is of httpd

Entries for the above mentioned site are added by successively defining ltVirtualHostgt ltVirtualHostgt block each for each of the above mentioned sites The code is given below

The following command must be run to refresh the changes made in the configuration file to the Operating System

service httpd restart

After successful implementation of above command our server is ready to use

3)ImplementationThe following sites were accessible through the web browser firefox in our case by typing in the name of the website in the url bar For example station49examplecom gives you the following display

Similarly the displays of sites made by us are given below in the following order nikeexamplecom reebokexamplecom ndtvexamplecom audiexamplecom

nikeexamplecom reebokexamplecom

ndtvexamplecom audiexamplecom

22 Installation amp configuration of Apache Encrypted Web Server (https)Apache can provide encrypted communications using the mod_ssl Apache module To make use of encrypted communications a client must request the https protocol which uses port 443 The configuration file for mod_ssl in Red Hat Enterprise Linux is etchttpconfdsslconf

1)Installation

The https related components can be installed by using YUM utility The package name for https is mod_ssl

The packages were successfully installed

2)ConfigurationConfiguring https involves making certificate for the encryption to implement This certificate is required to be implemented in etchttpdconfdsslconf

Here we first change our native directory to etcpkitlscerts Implementing SSL requires making certificate Here we make the certificate using make command by the name of certificatecrt as shown below While making certificate we fill the certificate details These details include name of country state organization email hostname etc

After compiling the certificate the necessary changes in the configuration file are made As we know the configuration file for https is etchttpdconfdsslconf We edit this file using VI text editor

As we see here the changes are made to the only two uncommented lines in the above screenshot to notify the exact path name and the certificate name to the configuration file The file is then savedThe successive step is to move the key file generated with the certificatecrt named certificatekey to the etcpkitlsprivate directory as mentioned in the configuration file

The httpd service is then restarted to refresh the changes made in the configuration file It should be noticed that when we restart the service we are asked for the passphrase by the shell This signifies that our Apache server is now secure

3)ImplementationThe encrypted Apache HTTP server enables the web browser to display a warning while entering a protected site This is shown below

Here we use a private handmade certificate This is not recognized by the browser until we add an exception for it by clicking on the link as shown above The certificate details can be seen as below

23 Installation and configuration of Domain Name System (DNS) Name server

A name server consists of a program or computer server that implements a name-service protocol It maps a human-recognizable identifier to a system-internal often numeric identification or addressing component

The most prominent types of name servers in operation today are the name servers of the Domain Name System (DNS) one of the two principal name spaces of the Internet The most important function of these DNS servers is the translation (resolution) of humanly memorable domain names and hostnames into the corresponding numeric Internet Protocol (IP) addresses the second principal Internet name space used to identify and locate computer systems and resources on the Internet

Configuration Files

varnamedchrootetcnamedconfvarnamedchrootvarnamedfzonevarnamedchrootvarnamedrzone

Type System V-managedDaemon usrsbinnamed

The following command must be run to refresh the changes made in the configuration file to the Operating System

service httpd restart

After successful implementation of above command our server is ready to use

3)ImplementationThe following sites were accessible through the web browser firefox in our case by typing in the name of the website in the url bar For example station49examplecom gives you the following display

Similarly the displays of sites made by us are given below in the following order nikeexamplecom reebokexamplecom ndtvexamplecom audiexamplecom

nikeexamplecom reebokexamplecom

ndtvexamplecom audiexamplecom

22 Installation amp configuration of Apache Encrypted Web Server (https)Apache can provide encrypted communications using the mod_ssl Apache module To make use of encrypted communications a client must request the https protocol which uses port 443 The configuration file for mod_ssl in Red Hat Enterprise Linux is etchttpconfdsslconf

1)Installation

The https related components can be installed by using YUM utility The package name for https is mod_ssl

The packages were successfully installed

2)ConfigurationConfiguring https involves making certificate for the encryption to implement This certificate is required to be implemented in etchttpdconfdsslconf

Here we first change our native directory to etcpkitlscerts Implementing SSL requires making certificate Here we make the certificate using make command by the name of certificatecrt as shown below While making certificate we fill the certificate details These details include name of country state organization email hostname etc

After compiling the certificate the necessary changes in the configuration file are made As we know the configuration file for https is etchttpdconfdsslconf We edit this file using VI text editor

As we see here the changes are made to the only two uncommented lines in the above screenshot to notify the exact path name and the certificate name to the configuration file The file is then savedThe successive step is to move the key file generated with the certificatecrt named certificatekey to the etcpkitlsprivate directory as mentioned in the configuration file

The httpd service is then restarted to refresh the changes made in the configuration file It should be noticed that when we restart the service we are asked for the passphrase by the shell This signifies that our Apache server is now secure

3)ImplementationThe encrypted Apache HTTP server enables the web browser to display a warning while entering a protected site This is shown below

Here we use a private handmade certificate This is not recognized by the browser until we add an exception for it by clicking on the link as shown above The certificate details can be seen as below

23 Installation and configuration of Domain Name System (DNS) Name server

A name server consists of a program or computer server that implements a name-service protocol It maps a human-recognizable identifier to a system-internal often numeric identification or addressing component

The most prominent types of name servers in operation today are the name servers of the Domain Name System (DNS) one of the two principal name spaces of the Internet The most important function of these DNS servers is the translation (resolution) of humanly memorable domain names and hostnames into the corresponding numeric Internet Protocol (IP) addresses the second principal Internet name space used to identify and locate computer systems and resources on the Internet

Configuration Files

varnamedchrootetcnamedconfvarnamedchrootvarnamedfzonevarnamedchrootvarnamedrzone

Type System V-managedDaemon usrsbinnamed

Similarly the displays of sites made by us are given below in the following order nikeexamplecom reebokexamplecom ndtvexamplecom audiexamplecom

nikeexamplecom reebokexamplecom

ndtvexamplecom audiexamplecom

22 Installation amp configuration of Apache Encrypted Web Server (https)Apache can provide encrypted communications using the mod_ssl Apache module To make use of encrypted communications a client must request the https protocol which uses port 443 The configuration file for mod_ssl in Red Hat Enterprise Linux is etchttpconfdsslconf

1)Installation

The https related components can be installed by using YUM utility The package name for https is mod_ssl

The packages were successfully installed

2)ConfigurationConfiguring https involves making certificate for the encryption to implement This certificate is required to be implemented in etchttpdconfdsslconf

Here we first change our native directory to etcpkitlscerts Implementing SSL requires making certificate Here we make the certificate using make command by the name of certificatecrt as shown below While making certificate we fill the certificate details These details include name of country state organization email hostname etc

After compiling the certificate the necessary changes in the configuration file are made As we know the configuration file for https is etchttpdconfdsslconf We edit this file using VI text editor

As we see here the changes are made to the only two uncommented lines in the above screenshot to notify the exact path name and the certificate name to the configuration file The file is then savedThe successive step is to move the key file generated with the certificatecrt named certificatekey to the etcpkitlsprivate directory as mentioned in the configuration file

The httpd service is then restarted to refresh the changes made in the configuration file It should be noticed that when we restart the service we are asked for the passphrase by the shell This signifies that our Apache server is now secure

3)ImplementationThe encrypted Apache HTTP server enables the web browser to display a warning while entering a protected site This is shown below

Here we use a private handmade certificate This is not recognized by the browser until we add an exception for it by clicking on the link as shown above The certificate details can be seen as below

23 Installation and configuration of Domain Name System (DNS) Name server

A name server consists of a program or computer server that implements a name-service protocol It maps a human-recognizable identifier to a system-internal often numeric identification or addressing component

The most prominent types of name servers in operation today are the name servers of the Domain Name System (DNS) one of the two principal name spaces of the Internet The most important function of these DNS servers is the translation (resolution) of humanly memorable domain names and hostnames into the corresponding numeric Internet Protocol (IP) addresses the second principal Internet name space used to identify and locate computer systems and resources on the Internet

Configuration Files

varnamedchrootetcnamedconfvarnamedchrootvarnamedfzonevarnamedchrootvarnamedrzone

Type System V-managedDaemon usrsbinnamed

ndtvexamplecom audiexamplecom

22 Installation amp configuration of Apache Encrypted Web Server (https)Apache can provide encrypted communications using the mod_ssl Apache module To make use of encrypted communications a client must request the https protocol which uses port 443 The configuration file for mod_ssl in Red Hat Enterprise Linux is etchttpconfdsslconf

1)Installation

The https related components can be installed by using YUM utility The package name for https is mod_ssl

The packages were successfully installed

2)ConfigurationConfiguring https involves making certificate for the encryption to implement This certificate is required to be implemented in etchttpdconfdsslconf

Here we first change our native directory to etcpkitlscerts Implementing SSL requires making certificate Here we make the certificate using make command by the name of certificatecrt as shown below While making certificate we fill the certificate details These details include name of country state organization email hostname etc

After compiling the certificate the necessary changes in the configuration file are made As we know the configuration file for https is etchttpdconfdsslconf We edit this file using VI text editor

As we see here the changes are made to the only two uncommented lines in the above screenshot to notify the exact path name and the certificate name to the configuration file The file is then savedThe successive step is to move the key file generated with the certificatecrt named certificatekey to the etcpkitlsprivate directory as mentioned in the configuration file

The httpd service is then restarted to refresh the changes made in the configuration file It should be noticed that when we restart the service we are asked for the passphrase by the shell This signifies that our Apache server is now secure

3)ImplementationThe encrypted Apache HTTP server enables the web browser to display a warning while entering a protected site This is shown below

Here we use a private handmade certificate This is not recognized by the browser until we add an exception for it by clicking on the link as shown above The certificate details can be seen as below

23 Installation and configuration of Domain Name System (DNS) Name server

A name server consists of a program or computer server that implements a name-service protocol It maps a human-recognizable identifier to a system-internal often numeric identification or addressing component

The most prominent types of name servers in operation today are the name servers of the Domain Name System (DNS) one of the two principal name spaces of the Internet The most important function of these DNS servers is the translation (resolution) of humanly memorable domain names and hostnames into the corresponding numeric Internet Protocol (IP) addresses the second principal Internet name space used to identify and locate computer systems and resources on the Internet

Configuration Files

varnamedchrootetcnamedconfvarnamedchrootvarnamedfzonevarnamedchrootvarnamedrzone

Type System V-managedDaemon usrsbinnamed

22 Installation amp configuration of Apache Encrypted Web Server (https)Apache can provide encrypted communications using the mod_ssl Apache module To make use of encrypted communications a client must request the https protocol which uses port 443 The configuration file for mod_ssl in Red Hat Enterprise Linux is etchttpconfdsslconf

1)Installation

The https related components can be installed by using YUM utility The package name for https is mod_ssl

The packages were successfully installed

2)ConfigurationConfiguring https involves making certificate for the encryption to implement This certificate is required to be implemented in etchttpdconfdsslconf

Here we first change our native directory to etcpkitlscerts Implementing SSL requires making certificate Here we make the certificate using make command by the name of certificatecrt as shown below While making certificate we fill the certificate details These details include name of country state organization email hostname etc

After compiling the certificate the necessary changes in the configuration file are made As we know the configuration file for https is etchttpdconfdsslconf We edit this file using VI text editor

As we see here the changes are made to the only two uncommented lines in the above screenshot to notify the exact path name and the certificate name to the configuration file The file is then savedThe successive step is to move the key file generated with the certificatecrt named certificatekey to the etcpkitlsprivate directory as mentioned in the configuration file

The httpd service is then restarted to refresh the changes made in the configuration file It should be noticed that when we restart the service we are asked for the passphrase by the shell This signifies that our Apache server is now secure

3)ImplementationThe encrypted Apache HTTP server enables the web browser to display a warning while entering a protected site This is shown below

Here we use a private handmade certificate This is not recognized by the browser until we add an exception for it by clicking on the link as shown above The certificate details can be seen as below

23 Installation and configuration of Domain Name System (DNS) Name server

A name server consists of a program or computer server that implements a name-service protocol It maps a human-recognizable identifier to a system-internal often numeric identification or addressing component

The most prominent types of name servers in operation today are the name servers of the Domain Name System (DNS) one of the two principal name spaces of the Internet The most important function of these DNS servers is the translation (resolution) of humanly memorable domain names and hostnames into the corresponding numeric Internet Protocol (IP) addresses the second principal Internet name space used to identify and locate computer systems and resources on the Internet

Configuration Files

varnamedchrootetcnamedconfvarnamedchrootvarnamedfzonevarnamedchrootvarnamedrzone

Type System V-managedDaemon usrsbinnamed

The https related components can be installed by using YUM utility The package name for https is mod_ssl

The packages were successfully installed

2)ConfigurationConfiguring https involves making certificate for the encryption to implement This certificate is required to be implemented in etchttpdconfdsslconf

Here we first change our native directory to etcpkitlscerts Implementing SSL requires making certificate Here we make the certificate using make command by the name of certificatecrt as shown below While making certificate we fill the certificate details These details include name of country state organization email hostname etc

After compiling the certificate the necessary changes in the configuration file are made As we know the configuration file for https is etchttpdconfdsslconf We edit this file using VI text editor

As we see here the changes are made to the only two uncommented lines in the above screenshot to notify the exact path name and the certificate name to the configuration file The file is then savedThe successive step is to move the key file generated with the certificatecrt named certificatekey to the etcpkitlsprivate directory as mentioned in the configuration file

The httpd service is then restarted to refresh the changes made in the configuration file It should be noticed that when we restart the service we are asked for the passphrase by the shell This signifies that our Apache server is now secure

3)ImplementationThe encrypted Apache HTTP server enables the web browser to display a warning while entering a protected site This is shown below

Here we use a private handmade certificate This is not recognized by the browser until we add an exception for it by clicking on the link as shown above The certificate details can be seen as below

23 Installation and configuration of Domain Name System (DNS) Name server

A name server consists of a program or computer server that implements a name-service protocol It maps a human-recognizable identifier to a system-internal often numeric identification or addressing component

The most prominent types of name servers in operation today are the name servers of the Domain Name System (DNS) one of the two principal name spaces of the Internet The most important function of these DNS servers is the translation (resolution) of humanly memorable domain names and hostnames into the corresponding numeric Internet Protocol (IP) addresses the second principal Internet name space used to identify and locate computer systems and resources on the Internet

Configuration Files

varnamedchrootetcnamedconfvarnamedchrootvarnamedfzonevarnamedchrootvarnamedrzone

Type System V-managedDaemon usrsbinnamed

After compiling the certificate the necessary changes in the configuration file are made As we know the configuration file for https is etchttpdconfdsslconf We edit this file using VI text editor

As we see here the changes are made to the only two uncommented lines in the above screenshot to notify the exact path name and the certificate name to the configuration file The file is then savedThe successive step is to move the key file generated with the certificatecrt named certificatekey to the etcpkitlsprivate directory as mentioned in the configuration file

The httpd service is then restarted to refresh the changes made in the configuration file It should be noticed that when we restart the service we are asked for the passphrase by the shell This signifies that our Apache server is now secure

3)ImplementationThe encrypted Apache HTTP server enables the web browser to display a warning while entering a protected site This is shown below

Here we use a private handmade certificate This is not recognized by the browser until we add an exception for it by clicking on the link as shown above The certificate details can be seen as below

23 Installation and configuration of Domain Name System (DNS) Name server

A name server consists of a program or computer server that implements a name-service protocol It maps a human-recognizable identifier to a system-internal often numeric identification or addressing component

The most prominent types of name servers in operation today are the name servers of the Domain Name System (DNS) one of the two principal name spaces of the Internet The most important function of these DNS servers is the translation (resolution) of humanly memorable domain names and hostnames into the corresponding numeric Internet Protocol (IP) addresses the second principal Internet name space used to identify and locate computer systems and resources on the Internet

Configuration Files

varnamedchrootetcnamedconfvarnamedchrootvarnamedfzonevarnamedchrootvarnamedrzone

Type System V-managedDaemon usrsbinnamed

3)ImplementationThe encrypted Apache HTTP server enables the web browser to display a warning while entering a protected site This is shown below

Here we use a private handmade certificate This is not recognized by the browser until we add an exception for it by clicking on the link as shown above The certificate details can be seen as below

23 Installation and configuration of Domain Name System (DNS) Name server

A name server consists of a program or computer server that implements a name-service protocol It maps a human-recognizable identifier to a system-internal often numeric identification or addressing component

The most prominent types of name servers in operation today are the name servers of the Domain Name System (DNS) one of the two principal name spaces of the Internet The most important function of these DNS servers is the translation (resolution) of humanly memorable domain names and hostnames into the corresponding numeric Internet Protocol (IP) addresses the second principal Internet name space used to identify and locate computer systems and resources on the Internet

Configuration Files

varnamedchrootetcnamedconfvarnamedchrootvarnamedfzonevarnamedchrootvarnamedrzone

Type System V-managedDaemon usrsbinnamed

23 Installation and configuration of Domain Name System (DNS) Name server

A name server consists of a program or computer server that implements a name-service protocol It maps a human-recognizable identifier to a system-internal often numeric identification or addressing component

The most prominent types of name servers in operation today are the name servers of the Domain Name System (DNS) one of the two principal name spaces of the Internet The most important function of these DNS servers is the translation (resolution) of humanly memorable domain names and hostnames into the corresponding numeric Internet Protocol (IP) addresses the second principal Internet name space used to identify and locate computer systems and resources on the Internet

Configuration Files

varnamedchrootetcnamedconfvarnamedchrootvarnamedfzonevarnamedchrootvarnamedrzone

Type System V-managedDaemon usrsbinnamed

Ports 53(named) 953(rndc)

The Domain Name System (DNS) is a hierarchical naming system for computers services or any resource connected to the Internet or a private network It associates various information with domain names assigned to each of the participants Most importantly it translates domain names meaningful to humans into the numerical (binary) identifiers associated with networking equipment for the purpose of locating and addressing these devices worldwide An often-used analogy to explain the Domain Name System is that it serves as the phone book for the Internet by translating human-friendly computer hostnames into IP addresses For example wwwexamplecom translates to 19203210 DNS is also known as a distributed database that provides mapping between IP addresses and Host names

The Domain Name System makes it possible to assign domain names to groups of Internet users in a meaningful way independent of each users physical location Because of this World Wide Web (WWW) hyperlinks and Internet contact information can remain consistent and constant even if the current Internet routing arrangements change or the participant uses a mobile device Internet domain names are easier to remember than IP addresses such as 20877188166 (IPv4) or 2001db81f706e8 (IPv6) People take advantage of this when they recite meaningful URLs and e-mail addresses without having to know how the machine will actually locate them

The Domain Name System distributes the responsibility of assigning domain names and mapping those names to IP addresses by designating authoritative name servers for each domain Authoritative name servers are assigned to be responsible for their particular domains and in turn can assign other authoritative name servers for their sub-domains This mechanism has made the DNS distributed and fault tolerant and has helped avoid the need for a single central register to be continually consulted and updated

In general the Domain Name System also stores other types of information such as the list of mail servers that accept email for a given Internet domain By providing a worldwide distributed keyword-based redirection service the Domain Name System is an essential component of the functionality of the Internet

A hostname is a label that is assigned to a device connected to a computer network and that is used to identify the device in various forms of electronic communication such as the World Wide Web e-mail or Usenet Hostnames may be simple names consisting of a single word or phrase or they may include the name of a Domain Name System (DNS) domain at the end that is separated from the host specific label by a full stop (dot) In the latter form a hostname is also called a domain name If the domain name is completely specified including a top-level domain of the Internet the hostname is said to be a fully qualified domain name (FQDN)

A fully-qualified domain name (FQDN) sometimes referred to as an absolute domain name is a domain name that specifies its exact location in the tree hierarchy of the Domain Name System (DNS) It specifies all domain levels including the top-level domain relative to the root domain A fully-qualified domain name is distinguished by this absoluteness in the name space

For example given a device with a local hostname myhost and a parent domain name examplecom the fully-qualified domain name is written as myhostexamplecom This fully-qualified domain name therefore uniquely identifies the host mdash while there may be many resources in the world called myhost there is only one myhostexamplecom

In the Domain Name System and most notably in DNS zone files a fully-qualified domain name is specified with a trailing dot For example somehostexamplecom

Specifies an absolute domain name which ends with an empty top level domain label

The DNS root domain is unnamed which is expressed by an empty label resulting in a domain name ending with the dot separator However many DNS resolvers will process a domain name that contains a dot in any position as being fully qualified or add the final dot needed for the root of the DNS tree Resolvers will process a domain name without a dot as unqualified and automatically append the systems default domain name and the final dot

Some applications such as web browsers will try to resolve the domain name part of a Uniform Resource Locator (URL) if the resolver cannot find the specified domain or if it is clearly not fully qualified by appending frequently used top-level domains and testing the result Some applications however never use trailing dots to indicate absoluteness because the underlying protocols require the use of FQDNs such as Simple Mail Transfer Protocol (e-mail)

Structure

The domain name space

The hierarchical domain name system organized into zones each served by a name server

The domain name space consists of a tree of domain names Each node or leaf in the tree has zero or more resource records which hold information associated with the domain name The tree sub-divides into zones beginning at the root zone A DNS zone consists of a collection of connected nodes authoritatively served by an authoritative nameserver (Note that a single nameserver can host several zones)

Administrative responsibility over any zone may be divided thereby creating additional zones Authority is said to be delegated for a portion of the old space usually in form of sub-domains to another nameserver and administrative entity The old zone ceases to be authoritative for the new zone

1)Installation

You may install caching and bind in the DNS server as shown below

2)Configuration

After installation of bind and caching on the DNS serverGo to the configuration file and follow the steps shown below

Open namedrfc1912zones file

Copy content line no21 to 31 of namedrfc1912zones to namedconf

Now copy localhostzone to fzone in varnamedchrootvarnamed and namedlocal to rzone in same path

This is how fzone and rzone would look like after modificationsHere we have set ldquoexamplecomrdquo as the domain name

Now you may try pinging all sites made in apache

CONCLUSION

In our projecthellip

Apart from the regular curriculum we tried our level best to experiment on the topics and managed to achieve the following

Successfully configured DNS and APPACHEWe can host multiple sidersquos on single IPScheduled to access the sides from local system to remote systemWe have shown an elaborate configuring of the PROXY SERVER

SuccesshellipApache helped to support DNS with its web serving featuresDNS maintained the link between IP Addresses and Domain namesWe successfully managed to create a LAN and configure PROXY SERVEREven though we were working on a small network at our home and collegewe had a delightful and complete experience of networking

Our LimitationshellipWorking on a small network which was not registered with the ISP restricted us from multiple websites to the best sites existing today like yahoocomgmailcometcBecause of time limitations we could not implement scheduling of websites to other systems on the network in our project

PLATFORM USED LINUX

Reference-

1 wwwgooglecoin

2 wwwwikipediaorg

3 Linuxorg

4 Redhatcom

References

Copy content line no21 to 31 of namedrfc1912zones to namedconf

Now copy localhostzone to fzone in varnamedchrootvarnamed and namedlocal to rzone in same path

This is how fzone and rzone would look like after modificationsHere we have set ldquoexamplecomrdquo as the domain name

Now you may try pinging all sites made in apache

CONCLUSION

In our projecthellip

Apart from the regular curriculum we tried our level best to experiment on the topics and managed to achieve the following

Successfully configured DNS and APPACHEWe can host multiple sidersquos on single IPScheduled to access the sides from local system to remote systemWe have shown an elaborate configuring of the PROXY SERVER

SuccesshellipApache helped to support DNS with its web serving featuresDNS maintained the link between IP Addresses and Domain namesWe successfully managed to create a LAN and configure PROXY SERVEREven though we were working on a small network at our home and collegewe had a delightful and complete experience of networking

Our LimitationshellipWorking on a small network which was not registered with the ISP restricted us from multiple websites to the best sites existing today like yahoocomgmailcometcBecause of time limitations we could not implement scheduling of websites to other systems on the network in our project

PLATFORM USED LINUX

Reference-

1 wwwgooglecoin

2 wwwwikipediaorg

3 Linuxorg

4 Redhatcom

References

Now copy localhostzone to fzone in varnamedchrootvarnamed and namedlocal to rzone in same path

This is how fzone and rzone would look like after modificationsHere we have set ldquoexamplecomrdquo as the domain name

Now you may try pinging all sites made in apache

CONCLUSION

In our projecthellip

Apart from the regular curriculum we tried our level best to experiment on the topics and managed to achieve the following

Successfully configured DNS and APPACHEWe can host multiple sidersquos on single IPScheduled to access the sides from local system to remote systemWe have shown an elaborate configuring of the PROXY SERVER

SuccesshellipApache helped to support DNS with its web serving featuresDNS maintained the link between IP Addresses and Domain namesWe successfully managed to create a LAN and configure PROXY SERVEREven though we were working on a small network at our home and collegewe had a delightful and complete experience of networking

Our LimitationshellipWorking on a small network which was not registered with the ISP restricted us from multiple websites to the best sites existing today like yahoocomgmailcometcBecause of time limitations we could not implement scheduling of websites to other systems on the network in our project

PLATFORM USED LINUX

Reference-

1 wwwgooglecoin

2 wwwwikipediaorg

3 Linuxorg

4 Redhatcom

References

Now you may try pinging all sites made in apache

CONCLUSION

In our projecthellip

Apart from the regular curriculum we tried our level best to experiment on the topics and managed to achieve the following

Successfully configured DNS and APPACHEWe can host multiple sidersquos on single IPScheduled to access the sides from local system to remote systemWe have shown an elaborate configuring of the PROXY SERVER

SuccesshellipApache helped to support DNS with its web serving featuresDNS maintained the link between IP Addresses and Domain namesWe successfully managed to create a LAN and configure PROXY SERVEREven though we were working on a small network at our home and collegewe had a delightful and complete experience of networking

Our LimitationshellipWorking on a small network which was not registered with the ISP restricted us from multiple websites to the best sites existing today like yahoocomgmailcometcBecause of time limitations we could not implement scheduling of websites to other systems on the network in our project

PLATFORM USED LINUX

Reference-

1 wwwgooglecoin

2 wwwwikipediaorg

3 Linuxorg

4 Redhatcom

References

CONCLUSION

In our projecthellip

Apart from the regular curriculum we tried our level best to experiment on the topics and managed to achieve the following

Successfully configured DNS and APPACHEWe can host multiple sidersquos on single IPScheduled to access the sides from local system to remote systemWe have shown an elaborate configuring of the PROXY SERVER

SuccesshellipApache helped to support DNS with its web serving featuresDNS maintained the link between IP Addresses and Domain namesWe successfully managed to create a LAN and configure PROXY SERVEREven though we were working on a small network at our home and collegewe had a delightful and complete experience of networking

Our LimitationshellipWorking on a small network which was not registered with the ISP restricted us from multiple websites to the best sites existing today like yahoocomgmailcometcBecause of time limitations we could not implement scheduling of websites to other systems on the network in our project

PLATFORM USED LINUX

Reference-

1 wwwgooglecoin

2 wwwwikipediaorg

3 Linuxorg

4 Redhatcom

References

PLATFORM USED LINUX

Reference-

1 wwwgooglecoin

2 wwwwikipediaorg

3 Linuxorg

4 Redhatcom

References

Page

95

96

• Fdisk usage
• Creating Three primary partitions with one Swap
• After doing the partition please reboot the computer or user following command to refresh the partition hard disk
• partprobe devhda
• Formatting the partition in Linux
• After creating the partition you need to format the partition for using the space Linux defaults using the ext2 or ext3 file system but we can also used fat file system in Linux
• 1 For format the partitation in ext3 file system use following commands
• mke2fs ndashj devhda4
• 2 For format the partitation in ext2 file system use following commands
• mke2fs devhda4
• 3 For format the partitation in FAT file system use following commands
• mke2fs vfat devhda4
• • Run Levels in Red Hat Linux and Fedora
  • • Types of FTP
    • • Figure Active And Passive FTP Illustrated
      • Active FTP
      • Passive FTP
      • Regular FTP
      • Anonymous FTP
      • • Connection methods
        • Criticisms of FTP
        • The vsftpdconf File
        • Apache HTTP Server
        • • Features
          • Features of Apache HTTP Server 20
          • Apache HTTP Secure Server Configuration
          • • An Overview of Security-Related Packages
            • • The BIND DNS Server
              • • Nameserver Zones
                • Nameserver Types
                • BIND as a Nameserver
                • • Configuration Files
                  • varnamedchrootetcnamedconf
                  • varnamedchrootvarnamedfzone
                  • varnamedchrootvarnamedrzone
                  • • Structure
                    • The domain name space
                    • • 1)Installation
                      • You may install caching and bind in the DNS server as shown below