I hit a stumbling block with adding compute nodes to new HPC cluster. If you see the following errors when deploying Microsoft HPC Pack 2012 R2 when joining compute nodes to the cluster:
HPC Node Manager Service unreachable
System.Runtime.Remoting.RemotingException: An error occurred while processing the request on the server: System.Runtime.Remoting.RemotingException: User identity is not authorized to connect to this endpoint
The solution is to add your installation credentials to the administrators group before install HPC pack on compute nodes.
Edit : Seems to be a bug in 2012R2 Update 2. Get your compute nodes to use short NetBIOS name for your cluster instead of fully qualified domain name. Worked for me.