CN2668Routers and SwitchesKemtis KunanuraksapongMSIS with DistinctionMCTS, MCDST, MCP, A+

Agenda•Chapter 5: Router and IOS Basics•Exercise•Quiz

Benefits of Routing•Routers provide

▫Packet filtering▫Connections between local networks▫Traffic control▫Wide area network (WAN) connections

•Routers operate at the Network layer of the OSI reference model▫Because of Network layer addressing,

routers can direct packets to both local and remote segments

Cisco Router User Interface•Cisco Internetwork Operating System (IOS)

▫Provides a command-line interface (CLI)•You can access a router in several different

ways▫Console port (also known as the console)▫Auxiliary port (AUX)▫Virtual terminals (VTY)▫Trivial File Transfer Protocol (TFTP) server▫See Figure 5-1 on Page 119

System Configuration Dialog•If the router has not been configured

previously, or if the startup file has been erased▫The Cisco IOS will prompt you to run the initial

configuration dialog after the router boots▫You also can type Setup to configure as well

•A series of prompts that guide you through the initial configuration for the router

•If IOS 12.0, you have two setups▫Basic management▫Extended setup

User Interface•The initial prompt:

▫The host name of the router followed by the greater than symbol (>)

▫Default: router>•User EXEC mode (User mode)

▫When the prompt displayed is the greater than symbol

▫User mode does not allow you to configure the router only to check status and review settings

User Interface (continued)•The question mark activates context-

sensitive Help on the Cisco router•Privileged EXEC mode

▫To enter privileged EXEC, you can type the enable command at the user mode prompt

▫Next, you may be prompted for a password▫Greater than symbol (>) changes to a

pound sign (#)

User Interface (continued)•The question mark activates context-

sensitive Help on the Cisco router•Privileged EXEC mode

▫To enter privileged EXEC, you can type the enable command at the user mode prompt

▫Next, you may be prompted for a password▫Greater than symbol (>) changes to a

pound sign (#)

User Interface (continued)•In Privileged EXEC mode

▫Setup command will cause the router to enter the system configuration dialog

▫Copy configurations can be copied from TFTP servers to the router and therefore change the router configuration

▫Erase configuration files as well as the entire IOS can be erased

Configuration Modes•Global configuration mode

▫Accessed by typing configure terminal at the enable mode prompt

•Interface configuration mode▫Allows you to configure the Ethernet and

serial interfaces on your router•Line configuration mode

▫Allows you to configure the virtual terminals, console, and AUX lines that let you access the router

Configuration Modes (continued)•Typing exit will take you back one level•Typing end or pressing the Ctrl+Z keys

will take you all the way back to the enable prompt

•Abbreviated commands▫Such as conf t, en, sh ru

•The router will show you the point at which you entered an incorrect character

Plethora of Passwords•5 passwords you can set

▫Enable▫Enable Secret▫Console▫Aux▫Virtual Terminal (VTY)

•Use service password-encryption if you want to encrypt all passwords

Plethora of Passwords•Enable Password and Enable Secret

Password configuration▫You can set both passwords from the global

configuration mode prompt▫You can type no enable secret and no enable password at the global configuration mode prompt To remove the enable secret and enable

passwords

Plethora of Passwords (continued)•Setting Line passwords

▫You can set passwords for each line used to configure the router

▫Configure the console line password Enter line con 0

▫You can also configure passwords on the five virtual terminal lines that exist on every router Enter line vty 0 4

Enhanced Editing•The enhanced editing commands let you jump

to the beginning or end of a command line▫You can also jump forward or back, character

by character, or word by word•You can turn off the enhanced editing features

by typing terminal no editing at either the user EXEC or the privileged EXEC prompts▫You can turn on terminal editing by typing terminal editing

•See Table 5-3 on Page 129

Command History•Command history

▫Allows you to retrieve previously typed commands

▫You can see up to 10 previously typed commands by typing show history

•To modify the number of commands stored by the router, you can use the terminal command▫Up to 256 previous commands▫Type terminal history size n

Configuring Router• Router host name

▫Default host name is router▫To set the router host name, type hostname followed

by the name that you want to set• Configure a banner

▫A banner is a message that you can configure to display each time someone attempts to log in to the router

▫Enter global configuration mode by typing config t Then type banner motd, followed by a space and a

delimiting character

Configuring Router (Cont.)•Configure an interface description

▫Use the description command▫The interface description helps you

remember which network the interface services

•Use the clock set command in enable mode to configure the time▫You must be in global configuration mode to

configure the time zone▫See Figure 5-14 on Page 132

Router Components•ROM

▫Contains the bootstrap▫Not modified during normal operations, but

it can be upgraded with special plug-in chips

•Flash memory (EPROM)▫Contains the working copy of the current

Cisco IOS▫Is the component that initializes the IOS for

normal router operations

Router Components (Cont.)•NVRAM

▫Contain the startup configuration file for the router and IOS uses it during boot process

•RAM/DRAM▫Changes to the router’s running

configuration take place in RAM/DRAM•Interfaces

Assignment•Review Questions

▫1 – 24•Case Projects

▫5•Lab 5.1, 5.3 – 5.5