Redundant 6509 throw flapping errors constantly

[jmf3186fj]

I have two 6509 connecting through etherchannel - I checked the logs on both switch and found about he same errors

Attached is the log of my situation

-JMF

[iyde]

A loop is happening somewhere in your network, causing the MAC adressess mentioned to be seen in rapid succession on PortChannel and then on a physical interfaces. Without more detailed knowledge of your network, it is difficult to say exactly what and where it happens - you will have to look in the logs of the switches in the other end of the mentioned interfaces.

HTH.

[Rui Carlos Antunes]

This can be caused by EtherChannel misconfiguration.

Can you post the configuration of the ports and of the EtherChannel on both switches, as well as the output of the "show etherchannel" command and of the "show interface trunk" for the ports involved in the EtherChannel?