Microsoft Knowledge Base Article 292541 contains the following summary:
Although you can rename a Windows 2000 domain in some situations that are described in this article, Microsoft highly recommends that you decide on the Fully Qualified Domain Name (FQDN) for DNS before you actually create a new domain or before you upgrade the domain from Windows NT 4.0 to Windows 2000. After you create the domain, you cannot rename a Windows 2000 domain controller. Renaming the domain involves a considerable amount of work, and it is only possible in a scenario that meets the following conditions:
| 1. | You have to keep the Windows 2000 domain in Mixed mode.
After you change it to Native mode, you cannot return the domain to Mixed mode,
thereby rendering renaming impossible. To determine the mode in which the
domain is currently running, expand Active Directory Users and Computers,
right-click the domain name, and then click
Properties
. The mode appears in the
Domain operation mode
dialog box.
For additional information about the different modes, click the following article number to view the article in the Microsoft Knowledge Base:
186153
Modes Supported by Windows 2000
Domain Controllers
|
| 2. | Because the domain is in Mixed mode, it must also either have one or more existing Windows NT 4.0 backup domain controllers (BDCs), or computers that are available to use as Windows NT 4.0 BDCs. |
Because you must demote all existing Windows 2000 domain controllers to member servers before you rename the domain controller, review the following information in terms of logistics:
| • | The renaming can only take place after you revert the domain back to Windows NT 4.0, and then during the upgrade to Windows 2000, after you have renamed it with the desired DNS (FQDN) name. The NetBIOS domain name remains the same. |
| • | If you have created one or more child domains, you have to revert the child domains back to Windows NT 4.0 first, and then revert the parent domain. Next, you rename the parent when you upgrade it to Windows 2000, and then you bring the child domain up again when you upgrade it to Windows 2000. The amount of time that this process requires depends on the number of Windows 2000 domain controllers that are in the domain, in addition to their physical location. |
