Recently I have decided to use a mixed group of operating systems (OS) in a server environment using VMware workstation. The first domain controller (DC1) OS is Windows Server 2008 R2 x64, and two NICs, one for NAT and the other local only. The second (DC2) is Windows Server 2008 x64 with a local only NIC. While dcpromo was running on the second machine, I received an error message similar to this one (I was replicating the error by joining the domain after taking down DC1):
Obviously, to many experts, this is a DNS issue. Clicking on Details lists various possibilities as to why it couldn’t contact the DNS server.
I checked the TCP/IP configuration of DC2, all was set; next was DC1, and there the DNS address was set to the loopback address, which always happen after the DNS role is installed. After reconfiguring that part, the error message would still pop-up. After all the rechecking, I stopped the dcpromo process. One last shot was to use the IPCONFIG command. I ran the ipconfig /flushdns command and restarted the dcpromo process. Well, guess what happened! The process went through…the second machine became DC2.
I tried replication the error on my third machine, a member server for WDS. The picture above belongs to this machine. Here’s what I did first:
Checking to make sure that the DNS address points to DC1, but the error still occurs. Next up is running the ipconfig /displaydns command:
From this picture there is no DNS record for the local only address of DC1, only the NAT. Therefore, there will be no communication between servers. I flushed the DNS cache and restarted the renaming and joining of the domain processes with better success.
Tek or Belly Up 