SW_MATM-4-MACFLAP: Flapping

[csasrinivasan]

Hi,

Can someone help with MAC flapping Issue in the Networks in 3 different Switches

I have attached the Screen Shot also

%SW_MATM-4-MACFLAP_NOTIF: Host 5254.4c83.09e0 in vlan 12 is flapping between port Gi1/0/19 and port Po1

I'm really confused why this happened, can anybody help me ?

Thanks..

[Mohsin Alam]

A MAC Flap is caused when a switch receives packets from two different interfaces with the same source MAC address.

If you are getting the behavior for a lot of other MACs, that most likely is a layer 2 loop.

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[Leo Laohoo]

Trace the MAC address starting from Gi1/0/19.

[balaji.bandi]

what is VLAN 12 ? is this anything related to Wireless ?  - if not we need more information to investigate or help

[csasrinivasan]

No it it Related to Hot Line koon tech Phones

[balaji.bandi]

Hope this  wired -  if it is wired need to investigate on that port.. (is the phone connected any where 2 Ethernet ?)

[csasrinivasan]

we are having 3 phones of same brand in different area, and the same port is having two mac addresses

[balaji.bandi]

I have seen this kind of MAC issue some other door controller one of the environment.

if this is not causing issue in the network, i will ignore and move on since known issue.

[csasrinivasan]

End Devices Phones are unable to communicate so is there any soultion

how to Stop learning the mac address on the port?

can you explain me what is use of enabling this command on the interface ?

spanning-tree bpduguard enable

[apogeenet]

Do any of your phones you mention have both ports connected to the wall?  Many budget friendly phones are also "loop friendly." Also look for the existence of an unmanaged switch hanging off a phone, then looped back to itself or connected another wall port.