I have a 3 node Windows Server 2012 R2 Failover Cluster, and I'm having trouble getting Cluster Aware Updating to work properly. I have been able to successfully apply updates that do not require a reboot, however, anytime I have updates thatdo require a reboot, the process fails. The error message says:
Failed to restart <ServerName>:(ClusterUpdateException) Failed to restart <ServerName>:(Win32Exception) The RPC server is unavailable ==> (Win32Exception) The RPC server is unavailable
I have verified that the firewall rule to allow automatic restarts is configured according to Technet: Requirements and Best Practices for Cluster-Aware Updating
I have also made sure that the CAU AD account has local admin rights, as well as "Force shutdown from a remote system" rights on each of the cluster nodes. In this case, I have been applying updates manually from my workstation (which is not a member of the cluster) while logged in with Domain Admin rights (as opposed to letting the cluster update itself based on a schedule). I'd like to verify that the entire process works properly before letting it update itself. What am I missing?