Cisco 1721 Config fastethernet

Posted on 2006-03-24
Last Modified: 2013-11-16
OK, I am new to the Cisco world not to mention the CLI. What I need is the command sequence to set the fastethernet IP and subnet.

I don't even know how to get into config mode so go through it step by step.. I know it can't be that hard.

Background info:

I was working in the web interface and removed the IP's from both NIC's and now I can't get in. However, I am able to log on to the CLI. If I can get the fastethernet nic to have an IP, I'll be able to get into a familiar interface again.
Question by:wanabegates
    LVL 14

    Accepted Solution

    telnet into the router

    type in the following:

    enable         ---->enter priviledge mode
    conf t          ----->enter configuration terminal
    interface fastethernet 0            ----->select the interface
    ip address  ---------->set the ip address and subnet using real values here
    no shutdown  --------->enable changes

    This should get you going


    LVL 14

    Expert Comment

    by:Juan Ocasio
    BTW each line above is followed by the enter key so you would type in enable <enter> , conf t <enter>, etc...

    LVL 11

    Expert Comment


    Here are the commands (abbreviations that work and full commands)

    From the router prompt enter

    en (enable)

    (enter Password)

    conf t (configure terminal)

    int f0/0  (interface Fastethernet 0/0 or whatever port you're configuring)
     description (optional, but nice)
     ip address  (for a class C address)
     no shutdown

    <Cntl Z>

    That's all you need for the interface. Now if your configuring routing (RIP, EIGRP, OSPF) there's more to it.


    LVL 27

    Expert Comment

    When you don't know what to type, or how, type ?

    If you know the beginning of the command, type the first letter or two and then ? to get a list of commands that begin with those letters.  When you've typed enough to be unique, you can hit the tab to have the command auto completed.

    Author Comment

    OK, I'm in! Thank you all for the great input. I know I have a ways to go in learing this router. I'll be setting up a VPN next to authenticate agains a  RADIUS server (win2k3) but that is another question!

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