[c-nsp] Mac address flapping..

[James Ashton]

I have looked at all the port configs in question.    No forgotten stuff that I can see.

I am willing to go with the loop idea..  But I dont get any loop errors.   I dont get any Mac Move errors other than for this HSRP Mac Address, and over 120 other vlans on  these same ports arent having this issue.


But if it were a loop, how would I find it and fix it..   I ahve gone through every method I know of and allt he Cisco troubleshooting docs.   I can feel that I am missing something here, But I just cant think of what.

James

________________________________________
From: Mateusz Blaszczyk [blahu77 at gmail.com]
Sent: Friday, July 10, 2009 3:19 PM
To: James Ashton
Cc: cisco-nsp at puck.nether.net
Subject: Re: [c-nsp] Mac address flapping..

James,

. (I have a pair doing redundant gateways for a DataCenter network)
>
>       %MAC_MOVE-SP-4-NOTIF: Host 00d0.009e.2400 in vlan 42 is flapping between port Po1 and port Gi1/7
>
> I see about 20 of these for this one vlan each minute.

the mac is 6509-b and pps==20/minute is probably HSRP hello packet
from Vlan42 on 6509-b.
if there are no topo changes in stp there must be a unnoticed L2 loop,
either forgotten portfast or bpdu filtering between 6509-a,-b and
4506-a.

perhaps try to disconnect the customer completely during a maintenance
window and double check all your connections.

Best Regards,

-mat