I am planning an upgrade to my server 2008 R2 to server 2012 r2 and wanted to check if my plan has a good chance of succeeding.
I have two DC's; DC1 is a server 2008 standard and holds all FSMO roles, DSN and DHCP ( it has no other significant functions). DC2 is a server 2008 r2 with DC, DSN roles along with some other important data applications.
I want to do an in place upgrade on DC2 to server 2012 r2 because 1) it is a very long and drawn out process to reinstall the applications and 2) the boss won't spring for a new machine right now.
I checked with the application vendors and they say I should not have any problems with an in place upgrade but I am not so sure about upgrading with the DC in place.
My question is an easy one: Would it be a good idea to just demote DC2, apply the upgrade and then promote it again?
Thanks in advance!
Best Answer
I'm not sure why @whizkid thinks Microsoft doesn't recommend in-place upgrades. That might have been the case way back in the 2000/2003 era of Windows. But ever since the Win7/2008R2 generation of Windows, in-place upgrades have been pretty well supported. In fact, it has basically become the new default for desktop OSes. Just look in the tech news for all of the annoyed reports from people getting auto-upgraded from Win7/8/8.1 to Win10.
I've personally performed a decent number (10+) of in-place upgrades from 2008 R2 to 2012 R2 on domain controllers in production environments without any issues whatsoever (aside from the expected downtime during the upgrade process). Admittedly, most of those were running nothing but DC related services. But in any case, I wouldn't let the fact that the machine is DC stop you from attempting an in-place upgrade. But as always, have backups just in case.