Host Flapping on Cisco 4507

[oscar.garcia88]

Hi!

Recently we faced this flapping log on 4507 device, after that, we faced packet loss on different services on other devices around the network.

[Leo Laohoo]

How many physical interfaces are part of Po 60 & Po 61?  Are there two physical ports? 

If there are two physical ports per EtherChannel, disable one physical port per Etherchannel.  Next, see if the "MAC flapping" has stopped or not. 

If it has stopped, this means someone has bundled the wrong ports around/the wrong way. 

[balaji.bandi]

Do you have a high-level network diagram of how these devices are connected, 

is these PO60 nd 61 going to the same switch on other ends?

@Leo Laohoo also suggested good one test it.

[oscar.garcia88]

Unfortunately, I could not diasble one physical port of the etherchannel at this moment, because I could affect some services on the network.

Appreciate your comments.

[Defututus]

Just check all interfaces for physical layer errors, check the log of all devices if some convergence occurred. Implement storm control, check if the spanning-tree loopguard is enabled. Check spanning-tree rootbridges, enable the logging of the spanning-tree events. Make sure that udld is enabled on all fiber interfaces. Make sure that the spanning-tree rootguard is enabled where it should be. Check if the bpduguard is enabled. I can se some VMWare virtualization. Make sure that the BPDU filter is enabled on vSwitches (Net.BlockGuestBPDU) This should help you minimize the impact and to investigate it further if it appears again.