Backup wireless controller fail somtimes for some SSID

[Husam]

Hi all,

I have setup of 2 wireless controllers, 5 SSID and 200 APs. 4 Topologies are bridged at EWC and one at AP. Everything is going and working well as all access points are active in the main wireless controller. But when some APs move to be active on the backup controller some SSIDs (bridged at EWC) don't work well sometimes for some users while other SSIDs keep working well.

I checked the path between two wireless controllers and all Topologies are reachable and synchronized.

I am using C5210 and software 09.21.06.0006 for both controllers

Anyone have an idea what could be wrong?!

Thanks in advance,
Husam

[Husam]

for time as well they are going at same min!

[Husam]

Hi,
It is same topology and same configuration as I made and synchronized it from man controller.

The problem come up when some APs moved to be active on the backup controller and that result in some users can connect to wireless network but they can not have access to to any resources in the network even the default getaway, but some other users keep working normally.

regards,
Husam

[Doug]

Also make sure the time between controllers is synced (even if you have NTP configured)