Should a DC that is providing DNS Services (AD integrated) have its NIC set to look to itself (loopback) for DNS or point to other DCs that run DNS?

It should point to itself for primary and another dns server as secondary. I have always used the actual ip not the 127.0.0.1. There used to be an issue known as "dns server becomes an island" when it pointed to itself for dns http://support.microsoft.com/kb/275278 but that problem was corrected in windows 2003.

Here is some other information regarding DC Client Settings: DNS Client Settings for Active Directory Domain Controllers http://www.anitkb.com/2010/06/dns-client-settings-for-active.html Visit: anITKB.com, an IT Knowledge Base.

If you have only DC, you can point the DNS to itself. Otherwise, you can point DNS to other DNS severs. In windows 2008, you can not going to experience any “island “ issues. Santhosh Sivarajan | MCTS, MCSE (W2K3/W2K/NT4), MCSA (W2K3/W2K/MSG), CCNA, Network+ Houston, TX This posting is provided AS IS with no warranties, and confers no rights. http://publications.sivarajan.com/

If you have only DC, you can point the DNS to itself. Otherwise, you can point DNS to other DNS severs. In windows 2008, you are not going to experience any “island “ issues. Santhosh Sivarajan | MCTS, MCSE (W2K3/W2K/NT4), MCSA (W2K3/W2K/MSG), CCNA, Network+ Houston, TX This posting is provided AS IS with no warranties, and confers no rights. http://publications.sivarajan.com/