Unanswered Question
Apr 26th, 2008


I have a problem with one our switch that showing the below messgae and the Port has been deactivated,

"20:55:19: Gi0/2 can't be brought up because it failed POST in loopback test"

Is the problem with the Hardware? please assist

I have this problem too.
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Hi, the POSt test is run to detect fatal and non-fatal errors, a fatal is when the switch can not operate and most likely will need to be RMA. You have a non-fatal error on you ports the LED should be amber since the port was disabled when it failed the POST test. I would say this is a minor hardware problem, Cisco suggest to switch to another working port if there is one available. You can do some troubleshooting, check the port configuration, confrim that all cables are in good working condition, check for problem with the device on the other end. have a look at the document below for more info. HTH


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