1Module 11

Configuring and Testing Your Network

2Objectives Roles of Router and Router Components Boot-up process Cisco IOS and Configuration file Cisco IOS modes Basic configuring router Examination Commands Managing file Recovery password

3Roles of a Router and Router components

4Roles of a Router

A router connects multiple networks. This means that it has multiple interfaces that each belong to a different IP network.

Each network that a router connects to typically requires a separate interface. These interfaces are used to connect a combination of both Local Area Networks (LANs) and Wide Area Networks (WANs)

5 The primary responsibility of a router is to direct packets destined for local and remote networks by:

Determining the best path to send packets Forwarding packets toward their destination

The interface that the router uses to forward the packet may be the network of the final destination of the packet (the network with the destination IP address of this packet), or it may be a network connected to another router that is used to reach the destination network.

Roles of a Router

6What is a Router?

CPU

RAM

Flash

NVRAM

BUS

ROM

Interfaces

7Router Components - CPU Router Components - CPU

8Router Components - RAM

Stores

Routers active configuration (running-config)

Routing tables

ARP cache

Fast-switching cache

Packet buffering (shared RAM)

Packet hold queues

Content is lost when power down or restart

9Router Components - Flash Erasable, re-programmable ROM. Holds the operating system image Cisco IOS. The router normally acquires the default IOS from

flash. Allows you to update software without removing and

replacing chips on the processor. Content remains when you power down or restart. Multiple versions of IOS software can be stored in

Flash memory.

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Router Components - NVRAM Nonvolatile random-access memory (NVRAM)

Store the startup configuration.

Content remains when you power down or restart

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Router Components - ROM Read-Only Memory (ROM) is used for permanently

storing startup diagnostic code (ROM Monitor).

Main tasks for ROM are hardware diagnostics during router bootup and loading the Cisco IOS software from flash to RAM.

ROMs are not erasable. They can only be upgraded by replacing the ROM chips in the sockets.

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Router Components - Interfaces

The interfaces are the router connections to the outside.

Three types of interfaces: LANs interfaces

WANs interfaces

Management ports (Console and Auxiliary)

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Internal Components of a 2600 Router

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Access Method to Cisco DevicesAccessing the Cisco IOS on a Device

There are several ways to access the CLI environment. The most usual methods are: Console Telnet or SSH AUX port

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Console port

Is also preferred over the auxiliary port for troubleshooting. It is used to set up the initial configuration of a router and to monitor it. Displays router startup, debugging, and error messages by default. Can also be used when the networking services have not been started or have

failed. Can be used for disaster and password recovery procedures.

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Console Port Connections

A rollover cable and an RJ-45 to DB-9 adapter are used to connect a PC to the console port.

Cisco supplies the necessary adapter to connect to the console port. The PC or terminal must support VT100 terminal emulation. Terminal emulation software such as HyperTerminal is usually used

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Connecting Console Interfaces To connect the PC to a router:

1. Configure terminal emulation software on the PC for: The appropriate com port 9600 baud 8 data bits No parity 1 stop bit No flow control

2. Connect the RJ-45 connector of the rollover cable to the router console port.

3. Connect the other end of the rollover cable to the RJ-45 to DB-9 adapter.

4. Attach the female DB-9 adapter to a PC.

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Connecting Console Interfaces

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Connecting Router LAN interfaces

LAN interfaces allow the router to connect to the Local Area Network media. This is usually some form of Ethernet. It could be some other LAN technology such as Token Ring or Asynchronous

Transfer Mode (ATM). The router is a host that communicates with the LAN via a hub or a switch:

use straight-through cable The router is connected directly to the computer or to another router: a

crossover cable is required.

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Connecting WAN Interfaces

Wide Area Network connections provide connections through a service provider to a distant site or to the Internet

With some types of WAN interfaces, an external device such as a CSU is required to connect the router to the local connection of the service provider.

With other types of WAN connections, the router may be directly connected to the service provider.

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WAN Interfaces

Synch: Serial DB-60, WIC

Asynchronous: DB-68 with octal cable, RJ-45.

T1, E1: DB-15, RJ-45 with CSU/DSU built-in.

ISDN: BRI: RJ-45 , PRI: same as T1, E1 interface.

POTS: RJ-45 with Modem build-in.

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Boot-up process

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Router Boot-up Process

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Router Boot-up Process

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Router Boot-up Process

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Examining the initial router bootup

The user has the option to enter setup mode. Purpose of the setup mode is to permit to install a

minimal configuration for a router, unable to locate a configuration from another source.

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Initial startup of Cisco routers

During the setup process, Ctrl-C can be pressed at any time to terminate the process.

no

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Router Boot-up ProcessVerifying Router Bootup Process

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Cisco IOS andConfiguration File

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IOS File System Overview

Routers and switches depend on software for their operation. The two types of software required are operating systems and

configuration. The operating system used in almost all Cisco devices is the Cisco

Internetwork Operating System (IOS). The software a router or switch uses is referred to as the configuration

file or the config, running-config and startup-config.

IOS (running)running-config startup-config IOS ios

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Cisco IOS

The IOS operational details vary on different internetworking devices, depending on the device's purpose and feature set.

The IOS image file itself is several megabytes in size and is stored in a semi-permanent memory area called flash.

The services provided by the Cisco IOS are generally accessed using a command line interface (CLI).

The Cisco IOS provides devices with the following network services: Basic routing and

switching functions Reliable and secure

access to networked resources

Network scalability

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IOS Naming Conventions

Examples of feature-set categories are: Basic A basic feature set for the hardware platform, for example IP and IP/FW Plus A basic feature set plus additional features such as IP Plus, IP/FW Plus, and

Enterprise Plus Encryption The addition of the 56-bit data encryption feature sets, such as Plus 56, to

either a basic or plus feature set. Examples include IP/ATM PLUS IPSEC 56 or Enterprise Plus 56. From Cisco IOS Release 12.2 onwards, the encryption designators are k8/k9:

k8 Less than or equal to 64-bit encryption in IOS version 12.2 and up k9 Greater than 64-bit encryption (on 12.2 and up)

A relocatable image is copied from flash into RAM to run. A non-relocatable image is run directly from flash.

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Configuration Files

Configuration Files

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Cisco IOS Mode

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Cisco IOS Modes

IOS Primary Modes

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IOS Configuration ModesIOS Configuration Modes

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Logging into the router

User EXEC mode Typical tasks include those that check the router status. In this mode, router configuration changes are not allowed.

Privileged EXEC mode Typical tasks include those that change the router configuration.

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IOS Command Structure

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Help in the router CLI

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Help in the router CLI

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Command Syntax Check

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CLI Hot Keys

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Editing and History Functions

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Router Command History

terminal history size: maximum number of commands is 256

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Basic ConfigurationUsing Cisco IOS

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Enter Global Configuration mode

Router#configure terminal Router(config)#

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Configuring a router name

A router should be given a unique name as one of the first configuration tasks.

This task is accomplished in Global Configuration Mode.

Router#config tRouter(config)#hostname TokyoTokyo(config)#

Mistake

Should be

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Configuring Router Passwords

Not recommended, clear text

Router(config)#enable secret Use this command instead, password is encryped

Encrypts the passwords above, but

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exitend

Using exit, end and Control-Z

Login Banners

A login banner is a message that is displayed at login and is useful for conveying messages that affect all network users.

A login banner should be a warning not to attempt login unless authorized.

Configuring Message-Of-The-Day (MOTD)

Host Name Resolution

Host name resolution is the process that a computer system uses to associate a host name with an IP address

Host names, unlike DNS names, are significant only on the router on which they are configured.

Router# ping 172.16.32.1Router# ping AucklandRouter# telnet 192.168.53.1Router# telnet Beirut Router# traceroute 192.168.89.1Router# traceroute Capetown

Host Name Resolution

Router(config)# ip domain-lookupRouter#vdc3Translating vdc3"...domain server (255.255.255.255) (Takes a few seconds) Translating vdc3"...domain server (255.255.255.255) (Takes a few seconds) Router(config)# no ip domain-lookupRouter#wreh Translating wreh"% Unknown command or computer name, or unable to find computer address

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Configuring Router Interfaces

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Configuring an Ethernet Interface

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Configuring a Serial Interface

PPP, HDLC, Frame relay

Real

LabDCE cable

DTE cable

DTE Cable DCE Cable

Configuring a Serial Interface

On serial links that are directly interconnected, as in a lab environment, one side must be considered a DCE and provide a clocking signal.

The clock is enabled and speed is specified with the clock rate command. How can you tell which end is the DTE and which end is the DCE?

Look at the label on the cable. Look at the connecter between the two cables - The DTE cable will

always be male and the DCE cable will always be female. Use the show controllers command!

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Router Interface Description

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Examination Command

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IOS Examination Commands

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IOS Examination CommandsExample of IOS Output

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IOS Examination Commands

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IOS Examination Commands

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IOS Examination Commands

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IOS Examination Commands

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Managing Cisco File

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Saving running to NVRAM

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Export file running to a .txt file

When using Windows, the TFTP server software must be running.

The copy can be performed from the console port or from a telnet session.

The telnet session can be performed on the same computer where the TFTP server is running (or to a different computer).

Router# copy flash tftp

Backup IOS with TFTP Server

Copying Configuration file to TFTP Server

A TFTP server will allow image and configuration uploads and downloads over the network.

The TFTP server can be another router, or it can be a host system.

Troubleshooting: Be sure you can ping the TFTP server.

Copying Configuration file to TFTP Server

Just double click on the shortcut Remember, TFTP is Trivial FTP:

No authentication No login No choice for directory Uses UDP and verified via a TFTP checksum (not TCP ACKs)

Cisco TFTP Server.lnk

TFTP Software and Servers

RAMIOS (running)running-config startup-

configIOS

copy startup-config tftpcopy tftp startup-config

copy running-config tftpcopy tftp running-config

copy flash tftpcopy tftp flash

Copying, Editing, and Pasting Configurations

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Password Recorvery

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Password Recovery(1)

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Password Recovery(2)

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Password Recovery(3)

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Good luck with this module!