LAN, Switching and Routing: No link between fiber converter and Catalyst 6500, works with Router 730

Discussion in 'Cisco' started by Hoffa, Jan 12, 2007.

  1. Hoffa

    Hoffa Guest

    Greetings all

    I have tried to find an answer to and issue like this before but
    without success.
    I've tried for some day now to get a fiber connection between an
    IMCnetworks MM850 GigabitTP<->Fiber converter up and running. The fiber
    is on my end connected to a SX SPF. When I connect the cable and enable
    the interface I get a LinkUp light on the media converter but no link
    on my Cat6500. I've tried different autodetect, negotiation and speed
    settings but nothing works. I've also tried different SPFs and switched
    As a final solution I plugged the fiber cable into our 7301 router,
    bypassing our Cat6500. After I set the port to "no negotiate auto" the
    link went up on the 7301.

    How can the same cable and same SPF work on the 7301 but not on my
    Cat6500? Is there some setting I'm missing here?

    Fredrik Hofgren
    Hoffa, Jan 12, 2007
    1. Advertisements

  2. Hoffa

    Peter Guest

    Hi Frederick,
    That certainly sounds like the problem, however one thing seems
    obvious to me, the Device you are trying to connect appears to NOT be
    doing any negotiation. This means you MUST set the Cisco device to not
    even ATTEMPT to autonegotiate, the settings should match between ends
    EXACTLY, so that the Cisco device does not even try to autonegotiate.

    From you comments about the 7301 connection working I would also check
    the Auto MDX (X-over), however I have seen this work both ways in no
    negotiate scenarios so I guess it depends on the exact H/W involved.

    Its not much but I hope it
    Peter, Jan 12, 2007
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.