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Switch Lights Blinking Fast

Unanswered Question
Feb 27th, 2009
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Can anyone tell me if there's a problem with lights on a switch (Model Doesn't Matter, Different VLANs) or I should say every switch blinking fast?

Thanks In Advance

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Mohamad Qayoom Fri, 02/27/2009 - 06:44
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Just check to see if there is a duplex mismatch.

mikegrous Fri, 02/27/2009 - 06:55
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if a switch is blinking like crazy and performace is slow or non exsistat id check for a loop. Is the performance degregated?

jpannorfi Fri, 02/27/2009 - 07:16
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Not blinking crazy and there are no performance issue.

Mohamad Qayoom Fri, 02/27/2009 - 07:24
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Do "sh int cou err" to see if there are any errors.

jpannorfi Fri, 02/27/2009 - 07:41
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This switch has been operational for about 5 years. There were some errors, but I cleared the counters and I don't see any errors for the last 20 minutes.

glen.grant Fri, 02/27/2009 - 14:47
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Find out what model then do a search in CCO for the model you have and what the LEDS mean on the front . I never use them other than to make sure it has power anyway .

Leo Laohoo Fri, 02/27/2009 - 16:15
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What is the color of the LED? Green or amber/red? Look at the status light (over on the left). Is it Green or Amber/Red?

Model does make alot of difference. The 2900/3500XL switch port LED goes red when line errors occur (such as duplex or speed mismatch). If amber/red is constantly on (as compared to occassional blinking), it means that the port(s) have failed (Loopback test failure) or spanning-tree port blocking.

For other models after this generation of switches, amber/red lights constantly on on the switch means either ports are error-disable, ports down due to Trunking mismatch, duplex/speed mismatch, etc, or spanning-tree port blocking.


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