need to resolve input and CRC errors on a Cisco 3512 switch

Posted on 2005-04-21
Last Modified: 2008-01-09
I have 3 Cisco 3512's going into a 3508 in one building.  On all 3 switches I have Dell GX270 PC's with Intel Gig/100 NIC's.  On one switch, which I also have a Xerox Phaser 8400 printer attached I am getting a whole lot of errors.  My users when logging onto the computers in the "bad" switch sometimes cannot log onto the domain or don't get all their drive mappings.  The printer sometimes doesn't print and also spits out connection errors.  Looking on this one switch I am getting errors on all my interfaces, many input and CRC errors along with overruns and ignored.  The errors I am getting are just on the fastethernet ports, not the gig "uplink" interface.  Is there anyway I can resolve this, is this a Cisco code problem?  Is the switch bad?  The switch is running version 12 of the IOS which I believe is the latest.  Any help would be greatly appreciated.
Question by:mcannet
    LVL 79

    Accepted Solution

    Is this something that just started, or has been going on for some time?
    Typically CRC and input errors point to physical layer issues like cable plant issues.
    If you're seeing collisions on any switchport interface, it would point to duplex mismatches. Symptoms are just exactly as you describe them.
    Have you rebooted the switch lately? It can't hurt.
    Are the switchports all set to 100/full duplex, or are the set to default "auto" ?
    If you hard-set the switch, then you must also hard set the NIC on the workstations
    If you hard-set the NIC on the workstations, but keep the switchport at auto, then you have problems.
    LVL 27

    Expert Comment

    ... what lrmoore said - he's right on! :)
    LVL 1

    Author Comment

    I am testing the duplex now and will get back to you.  It's just strange though that everything had been working fine with no errors and just recently the ports have been having a lot of trouble.
    LVL 32

    Expert Comment

    Check this field notice out to see if you qualify, apparently there has been some hardware problems with the switch
    models you are using.

    LVL 1

    Author Comment

    Ok, I will say that it was a duplex mismatch, the switch ports were being forced at 100 full and the workstations were auto auto.     I changed all the ports to auto auto all my workstations and printer are connected at auto-100 auto-full.  Thanks all.

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