Currently we have a NT 4.0 with one PDC and two BDCs. To upgrade to Windows 2000 with AD, I added another BDC, and after, synched with the PDC I took offline. Our Windows NT domain name is HQ. When I upgrade the PDC to Windows 2000 during AD installation it is asking for domain name. Am I supposed to use HQ or company.com? If I use company.com for domain, does that mean when I want to add a new computer to domain I should use this name or HQ? Thanks for your help.
The upgrade process will automatically use the pre-existing NetBIOS domain name of HQ. The domain name it is asking for is the company.com. When you add a new computer to the domain, you can actually use either one. The Windows 2000 servers will generally recognize the NetBIOS name. Usually, Windows 2000 machines will have an easier time locating the domain when you use the 'company.com.' Of course, if you are using the company.com, you will need to have it registered on the Internet.
Another note -- if you are upgrading an NT 4.0 PDC/BDC you will want to make sure that the FQDN of the NT 4.0 machine is either blank or matches what you are going to call the Active Directory.
For example, in Windows NT 4.0 domain you had a FQDN of MyCorp.com and the new AD is going to be called MyCompany.com. If you upgrade the NT 4.0 server as it is, the system will name the AD MyCompany.com as instructed but WILL NOT rename the FQDN of the server, so it remains server.MyCorp.com.
Since it is a DC, you cannot rename the domain OR the FQDN of the server. Since the AD and the FQDN of the DC do not match, NO server will be able to locate or authenticate against these machines. You will end up reinstalling.
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