A couple of years ago my PDC died. The only physical box in my environment and the one physical server died.
I was 2,700 miles away. I wasn’t going to be back any time soon, and stuff was broken. (Thankfully, customer data was on the Linux Webhosting environment, so nothing lost there, except their backups)
My setup involves 1 physical server, and about 14VM’s (on two physical hosts) The physical server does a number of things. In addition to being the PDC/Infrastructure Master, etc. It holds my backups, gives me a plase to run consoles for various management agents…etc.
It died. Rebooted after a power-failure in the hosted datacenter I was throwing good money away on. (don’t EVEN get me started)
Anyway, technical mumbo-jumbo.
Recovered the original DC as a domain member using the following steps:
1. On DC1, Remove network connection / boot host. *VERY* important…
2. On DC1, Force-removed secondary/tertiary active-directory servers. (DC3, DC4)
3. On DC1, run DCPROMO and removed Active Directory – (There were a couple of minor gotchas to do this – like an idiot I didn’t write them down, but they were easy fixes, easily googleable. (is too a word) This removes all AD membership and makes it a stand alone workstation.
4. Shut down DC1
5. On the new PDC (DC2) removed DC1 as an AD server.
6. On DC1, connect network, boot server.
7. Join DC1 to AD as a domain member.