EdVassie (2/5/2013)
If you are running SQL 2012 RTM or below, all the nodes in the cluster must use the same operating system. With SQL 2012 SP1 and above, you can add a Windows 2012 node to a Windows 2008 R2 cluster, and ultimately migrate the cluster to Windows 2012.
Ed, can you point me to some documentation on this? I found documentation on cross cluster migration of availability groups but that is a very different thing than allowing mixed nodes.