I work for a small company with one NT4 domain controller, which contains the network accounts (less than 50), of course, and serves as the main file server (primary domain controller [PDC] only, no backup domain controllers [BDCs] and one other NT4 member server). I am an MCP on NT4, but I am new to Windows 2000 Server. I've just purchased a Dell PowerEdge 4600 with Windows 2000 Server. What is the easiest way to replace the NT4 DC with the Win2k DC?
There are a few options. One route will be to first reinstall the Dell PowerEdge 4600 to be NT 4.0 and a BDC in your domain. Then promote the Dell to be the PDC. Take the old server, which is now a BDC, off the network. Just power it down and leave it alone for now. Then upgrade the PowerEdge 4600 to Windows 2000. This will have the added effect of installing DNS and Windows 2000 Active Directory. All of the machine accounts, user accounts, etc., will come along for the ride. If it all works out OK, you can erase the old NT 4.0 BDC and redeploy the server somewhere else. If something goes wrong, erase the Dell and put the old BDC on the network again. Promote the old BDC back to PDC and you have your NT 4.0 just as it was.
Another way to go (the one I would probably take, being partial to having a new domain with a pure Windows 2000 machine and not an upgrade) is to upgrade the existing PDC to Windows 2000. Then take the Dell machine and promote it to a Windows 2000 DC. You will then have to move all of the FSMOs (Flexible Single Master Operations) from the old PDC to this new server. Then you can get rid of the old PDC and all of your users and accounts will be there.
Risks are greater with the second option. First, if you want to fall back to NT 4.0, you had better have a good backup tape because you won't have an unaffected BDC like you had in the first option. Also, moving the FSMO objects can be a little strange for a newcomer. But following some directions from the KB article, Using Ntdsutil.exe to seize or transfer FSMO roles to a domain controller (Q255504), should clear up any huge stumbling blocks. You will be transferring the roles. Oh, and don't worry about the issues of being a Global Catalog server -- since this is your only DC, the problems don't apply.
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