Contingency for a Fuse server in case of fail

Hi there!

I'm building a structure composed of five Fuse servers, of which #1 is the domain, #2 is the contingency of the first, in case of fail, and all of them are part of a cluster for load balance.

My question is: how can i configure the servers #1 and #2 so the #2 take #1's place in domain controlling in case of fail, keeping the data between them synchronized, and the #2 still helps the load balance?