We have an environment with two Windows 2003 servers in remote sites that talk to one another via VPN. Today I went to incorporate a new Windows 2012 R2 server in the hope that I could get rid of one of the old servers. But no, it couldn't be simple could it? The current functional level is set to Windows 2000 so I had to stop the upgrade as it couldn't go further.
If I went ahead and elevated the domain functional level to Windows 2003 are there any risks?