Multiple Mac Address Flapping on SWITCH

salman-ahmad · ‎12-19-2012

Hi,

Our server switch (10.0.0.249) it is connected with cores switch with portchannel and now its was start broadcasting with three specific mac address.

Gi1/0/31 Gi1/0/7 (X.X.X.5441)

Gi 1/0/27 Gi1/0/19 (X.X.X.56C9)

Gi1/0/31 Gi1/0/32 (X.X.X.5541)

1/0/31 Po 30 (X.X.X.CCd6)

Po 30 1/0/6 (X.X.X.CCd6)

NOW GUIDE ME HOW TO RESOLVE THIS ISSUE WHAT COMMAND I HAVE CONFIGURED WRONG ON PORT CHANNEL

I HAVE ALSO ATTACHED THE LOGS OF SERVER(10.0.0.249) SWITCH WITH CORE SWITCH 3RD FLOOR AND NMS REPORT.

KIND REGARDS,

SALMAN AHMED

Santosh Kolte · ‎12-19-2012

Do u Configured Port channel on both side of Switches with same vlan both sides... ........ Mac flap jenarally occurs when there r Multiple Links up ... not blocked by STP..

port Po30 and port Gi1/0/6

Gi1/0/19 and port Gi1/0/36

..... find out..May be loop is There between these 2 uplinks... shut down one of them ......& check what happens..

salman-ahmad · ‎12-19-2012

What about the others

Gi1/0/31 Gi1/0/7 (X.X.X.5441)

Gi 1/0/27 Gi1/0/19 (X.X.X.56C9)

Gi1/0/31 Gi1/0/32 (X.X.X.5541)

Santosh Kolte · ‎12-19-2012

check out for loop

Rolf Fischer · ‎12-19-2012

Please also post the first byte of the mac-addresses to check if the I/G-Bit is set (unicast/multicast) and/or the U/L-Bit (globally unique/local).

Sorry, it's in the log-file.

"02" means locally administered. Talk to the Server-Guys. This might be for redundancy (NIC Teaming) or load sharing.

I found that, maybe it helps:

http://rizzitech.blogspot.de/2008/08/connecting-netapp-fas3020-to-cisco-4948.html

https://supportforums.cisco.com/thread/159479

HTH

Rolf