Collisions exceed threshold. Considered as loopback

[gregtrfs]

Hi,

I'm constantly getting port shutdowns on my 2970 switch due to the following error - HALF_DUX_COLISION_EXCEED_THRESHOLD. Not sure how to re-enable the port that has shutdown.Difficult to reboot due to core backbone switch.

Thanks

Gerg

[jackyoung]

You better check the remote end duplex and ensure both are full-duplex (if it supported). Or try to replace the UTP cable if the problem still exists.

From here to use "shutdown" at the interface then "no Shut" to reactivate it.

http://www.cisco.com/en/US/products/hw/switches/ps5206/products_command_reference_chapter09186a00805a8712.html#wp1944793

Hope this helps.

[pnschurr]

It's likey that the port is set to half-duplex (or is negotiating half duplex) while the connected device is running full duplex. The port just sees too many collisions.

peter