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Cisco 3548 Switch Failure

We have OpenVMS running on a Streams Environment OSI protocol connecting to a Cisco 3548 switch with fiber GBIC trunk ports. The ports display link lights, but network connection to a Windows NT 4.0 Server (Service Pack 6) with Allied Telesyn NICs (half-duplex) fails with LAN Connection Errors reported on DHCP Client Computers. However, when the Switch is bypassed, and directly connected to the Server, problem disappears. Do I have a duplex mismatch problem or IOS release issue?


Re: Cisco 3548 Switch Failure

Please post the switch config. and the screen capture of the log. It is difficult to determine the problem w/o sufficient information.

Duplex will not make the connection down but only affect the performance and lots of error.

For the IOS, we need to know what IOS you are using then further analyze the case.

Hope this helps.


Re: Cisco 3548 Switch Failure

You have to check to see how the switchports are configured , by default the speed is auto/auto , if the ports are hardcoded to a specific speed and duplex then you probably have a speed/duplex mismatch. Match both ends of the links , if nics are auto then the switchport should be auto . If the nics are hard set to a speed/duplex then you have to set the switchport the same.