I've been investigating some hostflapping issues on my switches and discovered that this was caused by 2 access points where a client was roaming in between.
These AP's are standalone installations.
Is there any setting which will prevent this hostflapping ?
It depends on the platform. It is disabled by default on the 6500 running native IOS. It is enabled on the 3750/3560/2960 platforms and cannot be disabled.
On the 6500, if it has mac address move notification enabled, you can disable it with the command "no mac address-table notification mac-move" command in the global config.
How to tell if it is enabled on the 6500:
#sh run | i notification
mac-address-table notification mac-move
How to disable it on the 6500:
(config)#no mac address-table notification mac-move
Again, on the 3750/3560/2960 platform you cannot disable this feature.
It's a 4506 model running IOS 12.2(25).
The system doesn't accept the command
Doesn't this "flapping" have an impact spanning tree on the system ?
Command in discussion is supported in 12.2(31)SG or later releases.
Please be aware, the recommended command just stops the switch from reporting mac-move notification and do NOT stop mac-move itself.
Mac-move should NOT have impact on the spanning-tree. In reverse, mac-move may be a symptom of Layer2 instability.
If have confirmed the mac-address reported belongs to a wireless client, and two ports in the error message are connecte to APs, then I believe this is an expected behavior/symptom.