cisco 1841 and loopback

Posted on 2012-08-30
Last Modified: 2012-09-17
I'd like to test my WIC card with a hard loopback. I plan to plug one end of my LAN cable into the T1 loopback plug and the other end into my Cisco 1841. I enables hdlc encapsulation and loopback dte and without the T1 loopback plug connected to the router, I see input and output packets incrementing. How do I use my hard loopback plug to correctly test my WIC card. Thx
Question by:biggynet
    LVL 22

    Accepted Solution


    Author Comment

    Yes. I already have the hard loopback plug. I need to figure out how to configure the Cisco 1841 to test with the loopback plug.
    LVL 14

    Assisted Solution

    I usually use PPP encapsulation.  Since PPP do handshaking, it detects a loop and will indicate a looped state when you do a "show interface Serialx/y"
    "Serialx/y is up, line protocol is down (looped)"

    I have not tried it with HDLC encapsulation, and I do not know if it is possible for it to detect hardware loops explicitly.  The link provided by mattvmotas depend on pings to the interface, but it checks if you receive the data correctly.

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