CISCO C2960S switch port flapping

[Arijit007]

Hi,

We are facing an issue, where we see our CAT 2960 switch is logging port flapping logs. It is happening for only one particular port. We checked and find no discards, it is in full duplex mode. Below are device version-

Model number : WS-C2960S-24TS-L
SW version- 12.2(58)SE2

Port flapping happening every 3-4 minutes and then it goes up. Please help on this as what could cause this issue and what we can check further to fix the issue.

Thanks! 

[Georg Pauwen]

Helloi,

the first thing I would do is check what is connected to that port. Could be a faulty NIC in the connected device. Or just a faulty cable as well. Connect something else (with a different cable) to that port and monitor if the port keeps flapping.

[paul driver]

Hello
Is this a access/trunk port- What type of device is attached to it?
I would suggest to check your cabling first  and then try to set speed/duplex to autonegotiate 

sh interface x/x 
sh interface xx switchport

[Leo Laohoo]

Kindly reconsider upgrading the firmware of the switch.  12.2(58)SE train is a terrible choice of version.

Post the complete output to the command sh interface <PORT> controller