Problems with PDC to DC conversion
I am a volunteer at a local school and have maintained an NT network for some years. When we converted all of our workstations to Win2k Pro, I upgraded the PDC (primary domain controller) to a DC (domain controller). Everything seems to work. However, when I try to join a new workstation to the domain, I get an error that it cannot find the domain. When I try to bring a new server online, I get an Active directory error.
I took the DC offline and promoted the BDC (backup domain controller) to PDC to regain control. What did we do incorrectly, and how should the conversion of the PDC to a DC be done? Can we recover the DC that I have offline, or do I have to rebuild it?
Windows 2000 and Active Directory rely heavily on DNS. It is most likely that your DNS or your Windows 2000 server's Fully Qualified Domain Name (FQDN) are incorrect. When you upgraded the PDC, did you remember to check that the FQDN for the NT PDC matched what you were going to call the Active Directory domain? For example, let's say the PDC was in the MyCorp domain and had a DNS suffix of MyComp.com. When you upgraded, you indicate the Active Directory is going to be called MyCompany.com. Well, the AD is called MyCompany.com -- BUT the PDC still thinks the name is MyComp.com. So, when other machines try to find the domain, they can't. This is a typical problem. To resolve it, on the PDC prior to upgrading, make sure that you change the DNS suffix of the system to match whatever you are going to call the AD domain.
Now, aside from that, you could be having a problem with DNS. You will need to make sure that all of the workstations are pointing to the same DNS. You will also need to check to see that the Windows 2000 machine is correctly registering all of the AD names in the DNS. You can use the NETDIAG.exe tool from the Windows 2000 Support Tools (on the Windows 2000 CD) to get started checking out the DNS networking.
This was first published in April 2003