Is it possible to have a 2003 DC in a domain with a 2008 functional level? I was under the impression that the functional level was limited by the lowest OS version of the DCs. Are there potential issues to watch out for if that is possible? Thank you!
3 Answers
Q: Is it possible to have a 2003 DC in a domain with a 2008 functional level?
A: No it isn't
https://technet.microsoft.com/en-us/library/cc787290(v=ws.10).aspx
No. If it were the other way around, it could work. There's no sane way to downgrade a domain functional level.
It depends on the functional level of the forest. The functional level limits the lowest level of OS.