We have a Cisco 4000 that does not see a fiber connection.

Posted on 2008-11-18
Last Modified: 2013-11-09
Cisco 4000 connected to a Cisco 3560G w/ a fiber converter that connects the wired SC class fiber to the mini-port of the 3560.

Both Ciscos see the connector but neither see the fiber signal.  We do see a light at both ends of connection.  

Is there something we missed or has to be done on the Cisco(s)?
Question by:ikeepon
    LVL 28

    Expert Comment

    Assuming that they are both running IOS, try putting this in the config for the interface on each side:
    speed nonegotiate

    If the 4000 is running CatOS, try putting that just on the 3560. If that doesn't do it I'l lookup up the equivalent command for Cat OS.
    LVL 32

    Expert Comment


    What kind of converter do you have? Is it fiber to copper? If so is it ethernet or Fast ethernet?

    harbor235 ;}

    Author Comment

    sc to a mini-fiber converter

    I'll try that suggestion
    LVL 1

    Expert Comment

    Ensure that the Trunk has been setup I have seen on Switchs and routers if the Trunk is not setup correctly, what does your config look like.
    LVL 28

    Accepted Solution

    Doesn't necessarily have to be a trunk unless he wants to push multiple vlans down the fiber.

    Author Closing Comment

    your on the right track

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