I have a domain that only has 2 domain controllers (both on 2008 Server). I have trusts with other domains, but I'm not sure what version of server they are using. I also have several other servers (SQL, WSUS, etc.) that are running other versions of Windows Server, but they are not domain controllers. Has anyone had any trouble raising the domain functional level to 2008 with a similar setup? I know all the books say that you can raise the functional level without issues as long as all the DCs in the domain are 2008. However, since there is no going back, I'd like to hear some "real world" scenarios if there are any. Besides the trusts with other domains, there are no other "trees" in our local domain.