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Catalyst Express 500 complains about undersize frames


The exact switch model is WS-CE500-24PC.

It claims, that devices connected to its ports are generating undersize frames. The connected devices are IP phones with PCs. Moreover I've got messages about undersize frames on Gigabit ports, which are configured as GigaChannel and are connected to another WS-CE500-24PC. The interface counters are showing, that a lot of undersize frames are received, not send. I think, that such big count of undersize frames severely degrades the performance of the switch. Is there any way to diagnose this problem?

PS When the same endpoints are connected to a "normal" switch, like 2950 or 3500, there is no any problematic frames counted in the output of the "sh controllers ethernet-controller" command.

Thanks and regards,



Re: Catalyst Express 500 complains about undersize frames

When the switch receives a 60-63-byte dot.1q encapsulated frame, it counts it as an undersize frame, but it will forward the frame correctly. There is not workaround for this issue, since the problem is not in the switch, the switch is only reporting that it is receiving this frames in the interface, the frames are generated by the connected device and not by the switch. If you do not experience network connectivity issues in the interface reporting this issue I believe that the issue can be consider as a cosmetic.

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