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loopback causing err disable in uplink ports

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Johnson Punniyalingam
Honored Contributor

loopback causing err disable in uplink ports

Hi guys,
can pls help to adv on the below issue on the following error, causing switch uplink to errstate

%PM-4-ERR_DISABLE: loopback error detected on Gi0/1, putting Gi0/1 in err-disable
Problems are common to all, but attitude makes the difference
2 REPLIES
Bruce Campbell_3
Valued Contributor
Solution

Re: loopback causing err disable in uplink ports


Some Cisco switches send keepalives
on ports, and if they see the keepalive
packet come back, they consider it a loop,
and block the port.

You may have a loop, or misconfigured
link aggregation is another possibility.

If you are sure there are no loops, you could
try turning keepalives off on the port.
I think you just set "no keepalive"
(but then you will lose loop detection,
unless you use spanning tree to block
loops)



Bruce Campbell
Director, Network Services
Information Systems and Technology
MC 1018
(519)888-4567 x38323
University of Waterloo, Waterloo, ON
Johnson Punniyalingam
Honored Contributor

Re: loopback causing err disable in uplink ports

Thanks,
Johnson
Problems are common to all, but attitude makes the difference