Getting ready to upgrade our 2008 R2 DC's to 2012 R2. Five of the eight servers are replacement servers (newer/better equipmnent). I have the OS's installed on the new equipment. My next step is to complete the ADPREP commands (forestprep & domainprep) and was wondering what the ramifications are of the commands. Does this affect the other domain controllers in any way, i.e. what might it screw up? In the event that something blows up, is there a way to downgrade? I'm just trying to understand the process and be prepared, in the event...
8 DC's - Domain & Forest functional level 2008 R2
8 DC's - Domain & Forest functional level 2012 R2