Chapter 4 Configuration IOS Management Commands Objectives Use the setup feature on a Cisco router Log into a router in both user and privileged modes Find commands by using the help facilities Use command on a router by using the editing command Set the router passwords identification and banners Configure an interface with IP addresses and subnet masks Copy the configuration to NVRAM CISCO IOS Cisco Router IOS IOS 12 0 IOS 12 2 Most Current Carry network protocols and functions Connect high speed traffic between devices Provide security Scalability Reliability Cisco Router User Interface Connecting to a Cisco Router Console No Password AUX Allows Modem Telnet Can t telnet unless password is set Connecting To A Cisco Router Internal Router Components RAM DRAM NVRAM Copy of the IOS ROM Startup config Flash Memory Working storage contains dynamic configuration Bootstrap Interfaces Auxiliary Ports Internal Router Layout Internetworking Operating System IOS Programs Running Config RAM DRAM Tables and Buffers NVRAM Flash Memory Startup Config OS Bringing up a Router Boot up process 1 POST 2 Looks for the Cisco IOS in Flash memory 3 IOS loads into RAM looks for a valid configuration startup config stored in nonvolatile RAM NVRAM 4 If a valid config is not found in NVRAM setup mode Setup Mode Basic Management Setup Enough to Allow Connectivity to Router Extended Setup p150 154 Global configuration Interface configuration Notation e0 e1 0 Command Line Interface Command Modes IOS provides a command interpreter user EXEC mode Connect to remote devices Temporarily changing terminal settings Basic tests System info Command Modes con t privileged EXEC Should be password protected Set operating parameters Global configuration config Affect the system as a whole Enable routing and bridging functions here Interface configuration config if Modify operation of sn interface Subinterface configuration config subif ROM Monitor Mode Break during load Logging into the Router User mode Router Used mostly to view statistics Privileged mode enable en command Router Used to view change router configuration Configuring Your Router Console Aux Telnet VTY TFTP Network Management Station Note Any configuration changes need to be placed into RAM Typing config mem or config net from a TFTP host will replace the current running config Overview of Router Modes Global changes config startup terminal running Network tftp config terminal or config t Changes made to running config DRAM Memory To change the startup config NVRAM config memory or config mem Configuration CLI Prompts router en router config router config interface xxx router config if Interfaces Sub interfaces Line Commands Routing Protocol Configurations Editing Help Features Editing Help Features Commands starting with a certain letter Router c clear clock configure connect copy Word help Command Enhanced Editing Commands p 161 162 Command syntax completion Command line navigation Ctrl z to end configuration mode Tab to complete a command Router Command History Gathering Basic Routing Information show version Results of sh version Setting the Passwords 5 passwords 1st two used to set your enable password Used to secure privileged mode Router enable Other three are used to configure a password for accessing user mode via console port auxiliary port Telnet Passwords Enable passwords Router config enable password cisco Only used in old routers don t bother Router config enable secret cisco Neither will work if both the same Auxiliary Password Console Password Telnet Password line vty 0 Login password xxxx No login disables the need to set password Encrypting Your Password Router config service password encryption secret already encrypted Enable Passwords en last resort Allows access to the router if the tacacs server down password secret use tacacs A password server used for all routers in the network some commands shown in text will not work in simulator Other Passwords User mode line 0 70 aux console tty vty x y service password encryption NB no service password encryption line aux 0 login password xxxxxx IOS 12 2 password must come before login line console 0 line vty 0 4 Default is 5 vty lines Use no login to bypass telnet password requirements Banners Types Exec Line activation Incoming To be displayed on reverse Telnet clients login motd Delimiting character Example banner login note the cr is needed You are connected to xyz router Router Interfaces Purpose 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 172 16 10 2 255 255 255 0 Router config if no shut Router config if int fa 0 0 Router config if media type 100BaseX MII Serial Interface Commands clock rate bandwidth entered in kilobits Note clock rate on only set on DCE Hostnames Descriptions Hostnames Router config hostname todd todd config Descriptions Atlanta config int e0 Atlanta config if description Sales Lan Viewing Saving Configurations Viewing Saving Configurations running config saved in DRAM 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 sh interface sh int e0 sh int s1 sh controllers sh controllers s 1 line up down protocol up down Chicago New York Boston Hartford Help http www uni net th docs CIM CIM 20Router 20Basics icnecon tent module1 mod1frameset html Summary Used the setup feature on a Cisco router Logged into a router in both user and privileged modes Found commands by using the help facilities Used command on a router by using the editing command Set the router passwords identification and banners Configured an interface with IP addresses and subnet masks Copied the configuration to NVRAM