Cisco Routers & IOS Introduction

Router Interface ● Serial cable ● Command line interface ● Efficient ● Fast ● Universal across all Cisco equipment ● Must know for CCNA ● Use PuTTY for the communication software

PuTTY

Connect to Router Be sure serial is clicked Then open

Connected to the Router Very exciting

Modes ● There are two primary command line modes ● EXEC or unprivileged mode – Command line prompt: RouterA> ● Privilege or enable mode – Command line prompt: RouterA# – Privileged mode also has a number of sub-modes ● RouterA (arguments)# ● Each mode has a number of commands ● Each command has a number of sub-commands

Help ? ● To figure what you can do from particular mode ● Type ? ● Type a command followed by ?

Help Example

Privilege Mode ● Conventions in the Lab ● Router names: RouterA, RouterB, RouterC, RouterD, etc. ● Router passwords: ciscoA, ciscoB, etc. ● Conventions in the real world ● Router names have some relavence ● Router passwords complicated and secret

Privilege Mode show ● show version ● show ip interface brief ● show ip route

Get Out of the Router ● exit

Cisco IOS Enable Mode Protected Mode Introduction

Entering Enable Mode ● RouterA> enable ● Password: ciscoA ● RouterA# ● This is referred to as “parent Mode”

Protected mode Show Commands RouterA#show ? (12 pages worth!) RouterA#show interface summary RouterA#show ip route RouterA#show arp

Configuration Mode ● Protected mode has many sub-mode We will always configure the router from a terminal.

Config Mode ● Enter configure mode two ways. You must type ctrl-z lock in your changes and get out of config mode.

Change the Router’s Name Change the Router’s Password

Designate a DNS Server

Configuring Interfaces ● Naming conventions – Ethernet 6/2 – Serial 0 – FastEthernet0

Configuring Interfaces Specify the interface Specify the IP address OOPs doesn’t understand CIDR notation Likes this Make sure the port is UP Commit the changes Check it out

Default Routing ● Cisco defaults to ip routing ● However it can be reset ● RouterC (config)# ip routing ● Before setting static routes

Configuring Static Routes ● You need – destination network address and mask – IP address of the router interface to that network RouterC#ip route net-address net-mask next-hop-address RouterC#ip route

Configure Static Routes

Config Files ● Cisco has 2 config files – running-config ● The current configuration controlling the router – startup-config ● The configuration the router will use upon reboot – show running-config – show startup-config

Saving a Configuration ● Saving a successful running configuration ● copy running-config startup-config ● Restoring a saved configuration ● copy startup-config running-config

Lab 1 In the Research Lab, create network traffic between two computers that includes a file transfer. Capture the packets using one of the methods described in the slides. Document your steps using screenshots and written explanations, include the commands used and the steps taken. Use a hub or use a switch configured for port mirroring Port Mirroring Commands on Cisco switch in the Research Lab enable sh monitor – to check for existing configurations conf t monitor session 1 source interface fa 0/4 (src port) monitor session 1 destination interface fa 0/1 (dst port) end – leave config mode sh monitor Clear port mirroring when done with the lab enable conf t no monitor session 1 sh monitor – to make sure the session the mirroring was cleared end