I have an active directory that I've inherited, where when the company moved to a new location, they just pulled their last AD server and left it there. When they got to the new location, they set up another AD server locally, and yet another one at a remote site where their other servers were hosted.
So far we've got AD1 that's completely unavailable, AD2 that's a physical server located at the office, and AD3 located at a hosted site.
When I got here, I created another AD server (AD4) to be the primary in the Vmware environment (because I wanted to re-purpose the physical server (AD2) the local AD server was on). It died a week ago, so when I got it fixed and brought it back up, I force removed domain services from it before putting it back on the network (because it wouldn't just remove through regular dcpromo without forcing it).
Now I have 3 AD servers (AD1, AD2, and AD3), stuck in my active directory, that won't delete, and keep adding themselves to the replication connections of my active AD servers (AD5 and AD6) (I built another AD server (AD6) at a new hosting site because we're leaving the old hosting site).
Ultimately I just want 2 AD servers, one here in my vmware environment (AD5) and one in the new hosting company (AD6), and to remove all the other AD servers that just don't exist anymore, and demote the AD server (AD4) in my old hosting site before it goes away.
Understand? :)