Relation between Cisco PoE switch port and interface down

[eeebbunee]

Hello Engineers and Professionals,

I am facing an issue about switch port up&down issue.

When I checked the logs, 

it looks like one of interface port keeps jumpling between up & down status and I guess inline power (PoE switch) is related.

I thought providing power and packet transfer are different matter when switch do their work, but somehow I need to shutdown the inline power for the issued port in order to resolve this issue.

Can you please explain why am I having this issue? 

[Flavio Miranda]

Hi

 Which device are connected to this port? Is it possible this device is trying to negociate power with switch, no succeeding and dropping traffic?

[eeebbunee]

The issued port 2/0/48 is connected to switch (ExtremeNetworks).

I have no idea why switch dropping traffics after failed power negotiation. Ever since I shutdown the power inline to Gi2/0/48, no more interface down happened.

I thought switching packet and providing power is different matter.

[Leo Laohoo]

Could be a cable issue or an IOS bug.