VM forest at Softlayer :: Win Server 2012 R2 :: DC, SQL Server and RDS Server. Joined SQL and RDS to DC no problem but cannot login as domain administrator or domain user, only as local admin. Both servers show as computers in the DC management snap-in. Both servers have the DC as first DNS entry. Can ping both ways and login to browse files on DC after login prompt credentials are entered. Cannot add domain user to either machine. Error at end is that DC cannot be contacted. Network discovery is on for all machines and firewalls off. Using Private Net for LAN comm.