School on Digital Radio Communications for...
Transcript of School on Digital Radio Communications for...
Linux OverviewMarx Jerez [email protected]
Alejandro Gonzalez [email protected] Diaz [email protected]
Los Andes University - FundaciteMérida - Venezuela
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
Until now, according to the networking world, we havestudied the details of the layer 1 of OSI model (physic layer)
One of ours aims is create an infrastructure to exchageinformation
In order to satisfy this, we need some network service, but before we need use a good platform to do it.
What is Linux?
Linux is the core of a operating system, the so called “kernel”. It executes the applications and interacts withthe hardware. It was written in 1991 by Linus Torvalds butnow include code of thousand of programmers around theworld.
This kernel is combined with many others applications andtools that all together form the operating system knownas Linux o GNU/Linux
http://www.lugatgt.org/articles/overview/
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
What are Distributions?
Currently, there are a lot of applications and programs to do different tasks and they are dedicated to satisfy differentpurposes: image processing, editors, communications, network services, etc.
Companies like Red Hat, Slackware, SUSE, Debian, etc.collect their own set of applications, modify the kerneland build an installation program.
This compilation of applications, kernels and installers are called distribution.
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
GPL
Gnu Public License: This license establish that any software developed under it can be used in any way, modified andcopied. But, you can not claim falsely that you wrote theentire application, and any change that you do must beshared with the community.
Linux kernel and it application is under GPL.
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
Who owns and control Linux?
There is not a single entity in charge of Linux or owns it.This is by and for hobbyists, hackers, and professionals worldwide. However, Linus does own the name, "Linux"
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
Why use Linux in wireless networks?
§ Stable operating system
§ Best cost – effective solution for: routers, AP, firewall, monitoring station, etc.
§ Easy remote administration and is not heavy to do it troughthe network
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
Linux Structure
Hardware
Kernel
Shells
Applications
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
The Kernel
1. Is the part of the O.S that interacts directly with the hardware.
2. Its main function is:- Memory management.- Computer access control.- Maintenance the file systems, interrupts management.- Error and IO services management. .
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
End of quantum- Time sharing
The Kernel
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
- Multitasking- Multiuser- Almost completely written in C.- TCP/IP- POSIX.
The Kernel
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
The Shell
1. Is the interface between the user and the O.S.2. Command interpreter.3. Read instructions and interpret them as programs
execution.. 4. Has its own program language.5. Controls how and when the instructions are
executed..
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
The Shell
§ sh UNIX standard shell (Bourne shell).
§ bash GNU Version of the standard shell.§ csh California shell.§ jsh Job shell (sh extension)§ ksh Korn shell.§ tcsh Improved version of csh.
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
Applicatins and Services
- Telnet, ssh - Firewalls- FTP - Router- NIS - DHCP- NFS - Print server- DNS - Communication server- WEB - O.S server- Data Bases - E-mail server - etc.
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
Installation, Booting andStopping Linux
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
Slackware 9.1 Installation First prompt: some special parameters§ Keyboards selection§ Login as root§ Disk partitions (fdisk)§ Setup menu§ Source installation selection§ Target installation selection (what partition)§ Packages selection§ Format partition (whether or not check)§ File system type selection§ Inode size
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
Partition information:
- Swap partition (type 82) = at least same RAM size.- Linux native (type 83) = All available space in disk.
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
- Load the kernel- Hardware check. Devices detection and creation- Start system processes.
- init process /etc/inittab
- File systems check- Mount file systems
Boot process
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
Init Configuration file "inittab"
id:3:initdefault:
#System initializationsi::sysinit:/etc/rc.d/rc.sysinit
.
.l3:3:wait:/etc/rc.d/rc 3
.
.
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
Boot process
Comando shutdownReinicio, detención o tareas administrativas de bajo nivel
- Envio de señal SIGTERM a los procesos.
- Bloqueo de login.
- Ejecución del procesos init en nivel 0. desmontaje de sistemas de archivos.
School on Digital Radio Communications for Research and Training in Developing Countries -
Febreary 2004
Stopping the system
Linux Basic Commands
School on Digital Radio Communications for Research and Training in Developing Countries
Febreary 2004
Files management
School on Digital Radio Communications for Research and Training in Developing Countries
Febrary 2004
hawee jose
graphics management
Reportgraphics1
manual
ls
rm graphics
lpr grafico1
cp graphics graphics/graphics
more report
cat report
tail report
mv report management/
wc report
Files management
School on Digital Radio Communications for Research and Training in Developing Countries
Febrary 2004
§ Exercise(1):§ Run the following commands:§ ls§ ls -l§ ls -a§ ls -la§ What do you look at in each command?§ more report.txt§ cat report.txt§ less report.txt§ tail report.txt
Files management
School on Digital Radio Communications for Research and Training in Developing Countries
Febrary 2004
§ Exercise (2):§ Run the following commands:§ cp report.txt report.txt.old§ mv report.txt.old report.txt.orig§ ls -a§ ls -la§ What do you look at in each command?§ more report.txt§ cat report.txt§ less report.txt§ tail report.txt tail –l 15 report.txt
Files management
School on Digital Radio Communications for Research and Training in Developing Countries
Febrary 2004
§ Exercise (3):§ Run the following commands:§ gzip report.txt§ gunzip report.txt.gz
§ wc report.txt§ diff report.txt report.txt.changed
Basic Unix Command
School on Digital Radio Communications for Research and Training in Developing Countries
Febreary 2004
Directory management
pwdmkdir graphicscd graphicscd ..rmdir graphics
home
luis
graphics
report
Search
find / -name .login -print
Directory management
School on Digital Radio Communications for Research and Training in Developing Countries
Febrary 2004
§ Exercise(1):§ Run the following commands:§ cd Return tu your local home § mkdir mydirectory§ cd mydirectory§ cp ../report.txt ./mydirectory§ cd ..§ rmdir mydirectory§ Does it work?§ rm -rf mydirectory
Directory management
School on Digital Radio Communications for Research and Training in Developing Countries
Febrary 2004
§ Exercise(1):§ Run the following commands:§ cd Return tu your local home § mkdir mydirectory§ cd mydirectory§ cp ../report.txt ./mydirectory§ cd ..§ rmdir mydirectory§ Does it work?§ rm -rf mydirectory
Finding things
School on Digital Radio Communications for Research and Training in Developing Countries
Febrary 2004
• grep, egrep, fgrep -- print lines matching a patternExample:grep string filename(s) • find -- search for files in a directory hierarchyExamplefind / -name “report.txt” –print• Locate -- Index and quickly search for files on your systemExample:locate httpd
About other people
School on Digital Radio Communications for Research and Training in Developing Countries
Febreary 2004
w -- Show who is logged on and what they are doing.who -- show who is logged onfinger username -- user information lookup programlast -1 username-- show listing of last logged in userstalk username -- talk to another userwrite username -- send a message to another user
About yourself
School on Digital Radio Communications for Research and Training in Developing Countries
Febreary 2004
whoami --- print effective useridfinger--- user information lookup programpasswd --- update a user's authentication tokens(s)ps -u yourusername --- report process statuskill PID --- terminate a processquota -v --- terminate a process
du filename --- estimate file space usagelast yourusername --- show listing of last logged in users