BASIC CONFIGURATION OF ROUTER

 Basic configuration of router:-

Routers can be configured from: Console terminal

Auxiliary port – externally, via modems

 Virtual terminals (Telnet) – after installation

INTERNAL CONFIGURATION COMPONENTS :

RAM:-

 Contains dynamic / running configuration

 NVRAM:-

 Contains backup of configuration (startup configuration)

 Flash:-

 Contains copy of Cisco IOS

 ROM :-

Contains a subset of IOS

 Contains bootable IOS image

 Interfaces :-

Network connections which packets enter/exit from routers, e.g. Ethernet, serial, BRI, Token Ring

 Console and auxiliary ports:-

 Main command-line interface used for configuration

ROUTER STARTUP SEQUENCE –

1. Bootstrap program loaded from ROM.

 2. Bootstrap runs the POST.

 3. Bootstrap locates IOS in Flash.

4. IOS is expanded and then loaded into RAM .

5. Once IOS is loaded into RAM, it looks for startup-config in NVRAM .

6. If found, the configuration is loaded into RAM .

ROUTER MODES :-

there are six mode in router but mainly used of them three modes.

1. User- mode.: Automatically enter this mode when router is turned on You can perform basic tasks, such as connect to remote devices, perform basic tests  .
    ,Prompt :is as  Router>.

   

   fig .user mode

2. Privileged Mode.: High-level testing commands Set operating parameters Command to enter : Router>enable  ,then show as  Prompt : Router#.

   

   fig- privilige  mode

   
                                                                     or
   By this mode we can check every configuration of router ,erase,reboot etc.
3. Global configuration mode :-  Commands apply to features that affect the system as a whole Enter from privileged EXEC mode with command :
   Router#config t,  Prompt : Router(config)# 

   

   fig- config mode

4.  Interface mode :-  Configure interface, such as Ethernet, serial Enter from global configuration mode with command : Router(config)#int e 0/0  Or Router(config)#int s 0/0 Prompt : Router(config-if)#
5. Rommon mode :-Provides router with a small subset of IOS and helps router boot if IOS not found in Flash Prompt : Rommon 1>
6. Setup mode :-Helps new user to create a configuration for the first time, via a series of questions Prompted at bootup or enter setup at
   router# prompt