Solved: MAC Address Flapping - Wireless

Philip T Kurien · ‎09-13-2010

Friends,

I am having an issue here (not serious i guess).

I have 4 Wisms running on a VSS setup. with 400 APs.

I have been receiving the following logs on the VSS

Sep 12 19:39:10: %MAC_MOVE-SW1_SP-4-NOTIF: Host 001c.bf81.b7bb in vlan 220 is flapping between port Po704 and port Po736

Sep 12 19:39:10: %MAC_MOVE-SW1_SP-4-NOTIF: Host 0024.c454.fac6 in vlan 212 is flapping between port Po735 and port Po736

These are just 2 logs that i have put in, but im getting many more of them.

vlan 220 and 212 are user vlans in the network.

Now, my guess is that they are clients roaming between access points connected to different controllers.

or if Im wrong, is there something serious that i need to look into.

Thanks,

Phil

Stephen Rodriguez · ‎09-13-2010

Phil,

Your guess is correct. In Wireless, the MAC-Flap notificaiton is 99.999% due to a client roaming between AP on different WLC.

HTH,
Steve

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View solution in original post

Stephen Rodriguez · ‎09-13-2010

Phil,

Your guess is correct. In Wireless, the MAC-Flap notificaiton is 99.999% due to a client roaming between AP on different WLC.

HTH,
Steve

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Please remember to rate useful posts, and mark questions as answered

Philip T Kurien · ‎09-13-2010

Thanks Steve,

On further investigation, ive found 90% of the macs showing up are wireless phones or iphones.

So i guess its ok.

Thanks for the help!

Phil

Vinay Sharma · ‎09-25-2011

Hello Philip,

Please mark the Question as Answered, if the provided information by Stephen is correct and it helped. By doing that others can take benefit as well.

Thanks,

Vinay Sharma

Community Manager – Wireless

Thanks & Regards

dhanraj80 · ‎07-31-2013

Hi Vinay Sir, I need your support for wireless issue.

I getting multiple mac flap error messge in cisco 4507 Core switch while my mobile clietnts roaming from one AP to another AP due to this my whole lan network goes down.

And im having cisco AIR-CT2504-K9 controller also.

Requesting you to kindly help me in this case.

Thanks

dhanraj poojari

geo · ‎05-21-2016

Dear Vinay,

i have the same issues, my network is very simply only2504 controller and one 10 ap when client is moving to different AP, i getting the mac flap massage in my switch, please help on this

Zain Khan · ‎03-27-2019

Can u tell where your DHCP is configure? if its not on WLC then APs are not getting IP address sometime or your DHCP server become unavailable for a while thus result in MAC flapping. check your DHCP server option in controller TAB of your WLC and verify the IP address. if you have a small number of APs then its better to configure it on WLC

Zain Khan
https://www.linkedin.com/in/forzain/