Sybex CCNA Chapter 6: Cisco’s IOS Instructor & Todd Lammle

Chapter 6 Objectives The Cisco router IOS Enhanced editing Administrative functions –Hostnames –Banners –Passwords –Interface descriptions Verifying your configuration 2

Cisco Router IOS Carries network protocols and functions Connects high-speed traffic between devices Adds security to control access Provides scalability for growth Supplies reliability

Connecting To A Cisco Router Cisco 2800 Cisco 1841

Bringing up a Router Boot-up process: 1: POST 2: Looks for the Cisco IOS from Flash memory 3: IOS loads & looks for a valid configuration; startup-configstartup-config stored in nonvolatile RAM (NVRAM) 4: If a valid config is not found in NVRAM: setup modesetup mode

Setup Mode Basic Management Setup Extended Setup Command-Line Interface

Configuration CLI Prompts Interfaces Sub-interfaces Line Commands Routing Protocol Configurations

Command-Line Interface (CLI) More flexible than setup mode. To use the CLI, just say No to entering the initial configuration dialog.

Subinterfaces Allow you to create logical interfaces within the router Router(config- if)#interface f0/0.1 Router(config-subif)#

Logging into the Router User mode: –Router> –Used mostly to view statistics Privileged mode: –Router# –Used to view & change router configuration

Overview of Router Modes Global changes: –config terminal or config t running-config –Changes made to running-config (DRAM) startup-config –To change the startup-config (NVRAM) config memory or config mem running-config Note: Any configuration changes need to be placed into RAM. Typing config mem or config net (from a TFTP host) will append the current running-config

Editing & Help Features

Commands starting with a certain letter Router#c? clear clock configure connect copy Enhanced Editing Commands Router-Command History Gathering Basic Routing Information –show version

Enhanced Editing Commands

Enhanced Editing Commands (cont.)

Router Command History

Gathering Basic Routing Information

Administrative Functions The administrative functions that you can configure on a router and switch are Hostnames Banners Password Interface descriptions

Hostnames & Descriptions Hostnames Router(config)#hostname todd todd(config)# Descriptions Atlanta(config)#int e0 Atlanta(config-if)#description Sales Lan

Banners Purpose Types –exec –incoming –login –motd Delimiting character

Setting the Passwords 5 passwords: –1st two used to set your enable password Used to secure privileged mode; Router>enable user –Other three are used to configure a password in user mode via: console port auxiliary port Telnet

Passwords Enable passwords Router(config)#enable password cisco Router(config)#enable secret cisco Auxiliary Password Console Password Telnet Password Encrypting Your Password Router(config)#service password- encryption

Interface Descriptions Setting descriptions on an interface is helpful to the administrator and, like the hostname, only locally significant. The description command is a helpful one because you can, for instance, use it to keep track of circuit numbers. Here’s an example: Atlanta(config)#int e0 Atlanta(config-if)#description Sales Lan Atlanta(config-if)#int s0 Atlanta(config-if)#desc Wan to Miami circuit:6fdda4321 You can view the description of an interface either with the show running-config command or the show interface command.

Router Interfaces Bringing up an Interface no shutdown shutdown show interface Configuring an IP Address on an Interface Router(config)#int e0 Router(config-if)#ip address Router(config-if)#no shut Serial Interface Commands clock rate & bandwidth (entered in kilobits)

Viewing, & Saving Configurations Viewing & Saving Configurations –running-config –running-config saved in DRAM –startup-config –startup-config saved in NVRAM copy run start sh run sh start erase startup-config

Verifying Your Configuration Tools: –show running-config –show startup-config –ping –show cdp nei detail –trace –telnet

Other Verification Methods Verifying with the show interface command –Router#show interface ? Verifying with the show ip interface command –Router#show ip interface –Router#show ip interface brief –Router#show controllers

Summary Go through all the written labs and review questions Review answers in class 28