Introduction to Basic Commands
before moving to basic configuration of a WAN side of a router , we will start with the LAN side
STEP 1:Connecting a Router
Setup the LAN network as shown ,computers have to connected the switch and the switch to the routerFor configuring a router we have to access the router at this point comes the console cable from any computer a console has to be connected to the router.only after configuring the initial configurations the router can be accessed through the switch(telnet)
[ Note :only for the initial configuration ]
STEP 2:Accessing a Router
After connecting the console cable to the router we could access the router.
but it requires an software for accessing the router which is called a terminal in all xp s it installed which is called a HYPER TERMINAL.in case of win 7 we could download it (Hyper terminal for win 7) or else by using a third party software called PUTTY .
for accseing the from if you are using xp
goto
--->START
--->All programs
---> Accessories
---> communication
--->Hyper terminal
HyperTerminal will open a dialog box, give a name (user defined) and click “ok”
Select the “COM” port to which the console cable is connected and click “ok”,
Default values are:
Bits per Second: 9600
Data Bits: 8
Parity: None
Stop Bits: 1
Flow Control: none
Click on “Restore Defaults” and click “ok”
Once HyperTerminal is ready, now switch on the Router.
After the Router boots-up completely, (on a new Cisco Router) it displays the following question:
--- System Configuration Dialog ---
Would you like to enter the initial configuration dialog? [Yes/no]:no
Would you like to terminate autoinstall? [yes]:
If you choose “Yes”, IOS will prompt Questions to gather the information to configure the Router, it is recommended to choose “no”, since we can configure the Router using IOS commands.
To configure Cisco Router IOS commands are used. There are different IOS modes for various configurations.
The IOS modes are:
1. User Mode:
Router>
Router is the default hostname and can be changed, ‘>’ symbol implies “User Mode”.
This is the first mode user interacts with the IOS. It is a restricted mode and support only a very few basic commands.
2. Privilege Mode
Router#
‘#’ symbol implies Privilege Mode”. This mode has full administrative rights. This mode is generally used for advance troubleshooting using ‘show’ and ‘debug’ command. This is also called as the EXEC mode.
3. Global Configuration Mode
Router(config)#
‘(config)#’ symbol implies “Global Configuration Mode”. Configuration of the Router starts from this mode. In this mode configurations that affect the complete router are given. Example, hostname of the router.
4. Interface Configuration Mode
Router(config-if)#
‘(config-if)#’ symbol implies “Interface Configuration Mode”. This mode is used to configure a specific interface.
The different types of interfaces are
1. LAN interface
a. Ethernet
b. Fastethernet
c. Gigabitethernet
2. WAN interface
a. Serial
Each interface is identified by a number. The first interface is numbered as 0 the second interface is numbered as 1 and so on. In a modular router the number is given as ‘module number/interface number’. Example 0/0
5. Line Configuration Mode
Router(config-line)#
‘(config-line)#’ symbol implies “Line Configuration Mode”. This mode is used to configure Telnet, Console and Auxiliary
6. Router Mode
Router(config-router)#
‘(config-router)#’ symbol implies “Router Mode”. This mode is used to advertise network under dynamic routing protocols.
1.CONFIGURING HOST NAME
Router>enable
Router#configure terminal
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#hostname RT1
RT1(config)#end
RT1#
2.CONFIGURING CLOCK
RT1#clock set 20:20:20 20 Jan 2008
00:10:10: %SYS-6-CLOCKUPDATE: System clock has been updated from 00:10:10
UTC Mon Mar 1 1993 to 20:20:20 UTC Sun Jan 20 2008, configured from console
by console.
verification
RT1#show clock
20:20:21.520 UTC Sun Jan 20 2008
3.INTERFACE CONFIGURATION
Hyderabad(config)#interface Ethernet 0
Hyderabad(config-if)#
Hyderabad(config-if)#ip address 192.168.1.1 255.255.255.0
Hyderabad(config-if)#no shutdown
Hyderabad(config-if)#exit
4. TELNET
(tel´net) (n.) A terminal emulation program for TCP/IP networks such as theInternet. The Telnet program runs on your computer and connects your PC to a server(Routers) on the network. You can then enter commands through the Telnet program and they will be executed as if you were entering them directly on the server console. This enables you to control the server and communicate with other servers on the network. To start a Telnet session, you must log in to a server by entering a valid username and password. Telnet is a common way to remotely control Web servers.
Telnet Client is used to connect to remote machine by using the Telnet protocol. For example, I'm an old fashion IT guy, and I still like to configure Cisco Switches/Routers using telnet. If you started to use Windows 7, you will notice that telnet is not enabled by default !! Don't panic, it is just a matter of few clicks and telnet will be enabled again.
Telnet Client allows a computer to connect to a remote Telnet server and run applications on that server. Once logged on, a user is given a command prompt that can be used as if it had been opened locally on the Telnet server's console. Commands that you type at the Telnet client command prompt are sent to the Telnet Server and executed there, as though you were locally logged on to a command prompt session at the server. Output from the commands that you run are sent back to the Telnet client where they are displayed for you to view.
When you first try to run a telnet command, Windows will informs you that telnet is not recognized as a command
To enable Telnet Client on Windows 7, follow these steps :
Click on Start then right click on Control Panel
From Control Panel, click on Programs
Under Programs and Features, click on Turn Windows Features on or off
From the Windows Features window, using the slider, scroll down till you reach Telnet Client, select the checkbox beside it, then click on OK
The selected feature will be installed.
Once it is installed, the Windows Features windows will be closed To confirm that Telnet is installed, open command prompt and type telnet /?
Configuring a telnet in a Router
Hyderabad(config)#line vty 0 4
Hyderabad(config-line)#
Hyderabad(config-line)#password zoom
Hyderabad(config-line)#login
Hyderabad(config-line)#exit
Accessing telnet through computer
Access using the default Telnet client
Windows has, by default, a telnet client accessible from a Command Prompt window invoking:c:\> telnet 192.168.0.90
Password : pass
type the default password pass and press ENTER.
C:\>telnet <IP address of router >
password : <password given at the time of telnet configuration>\
