WLC Failover (4.2.61 and higher)
Before WLC version 4.2.61 you should put an controller name at the primary WLC of the AP.
After this version, it’s possible to have the AP connected to one WLC and point to a second WLC of another Mobility Group !
The WLC’s must be aware of both WLC and their Mobility Groups.
At the CLI of the WLC configure the following :
WLC1 >config ap primary-base WLC1 AP1 10.77.244.210
WLC1 >config ap secondary-base WLC2 AP1 10.77.244.204
The syntax is :
WLC1>config ap secondary-base controller_name Cisco_AP [controller_ip_address]