We like to implement a 1:1 redundancy architecture with two controllers A and B. Some offices APs will use A as primary and B as secondary and other offices will use B as primary and A as secondary.
APs will run as Hybrid-REAP over the WAN, switching traffic locally on each branch office.
We are considering the purchase of a WISM model WS-SVC-WISM-1-K9 as controller A and it will be installed in a WS-C6513 switch.
Due several reason, controller B can not be another WS-SVC-WISM-1-K9 but a 5508 or 4408, 5508 preferably as can scalate to support more than 100 APs.
We aim as one controller being able to backup the other in case of a failure.
My main concern is if there are any know limitations to run a scheme where the primary and secondary controller are not the same model, and in particular WISM and 55xx, or WISM and 44xx series.
I would like to know if somebody has see an actual deployment as such working? We need to know that this architecture is possible before purchasing the card.