This is a bit odd but it has been happening ever since we have been using the Cisco wireless APs and the 2106 Controllers.
When ever the controller goes down, either through power outage or planned outage the APs lose connection and never reconnect until I go to the AP and physically unplug it and plug it back in.
Initially I ran everything through a trunked port and that seemed to work fine but after reading a news posting here I changed the ap-management, and management interfaces to separate non-trunked ports but it seems to still happen.
The APs plug into a switch that has 802.1x authentication enabled but the APs are using mac based authentication so the controller going down should not knock them off the correct vlan.
Any ideas here?