Additional Domain Operations
This section discusses a few miscellaneous domain controller manipulations:
Demoting a domain controller, including demoting the last domain controller in a domain
Renaming a domain controller
Renaming a domain
Demoting Domain Controller
Unlike NT PDCs and BDCs, Windows Server 2003 and Windows 2000 domain controllers can be demoted to become member servers. This demotion strips away the services involved with authenticating users and passing out group policies but does not affect the server's name or capability to support applications.
The domain controller must be able to communicate with its replication partners or it will refuse to accept demotion. If you pull the server off the wire then attempt to demote it, it will stubbornly refuse. In this situation, you are forced to reinstall Windows Server 2003 completely. Also, if the domain itself remains available, you must run metadata cleanup from the Ntdsutil utility to clean out the server name from Active Directory. See Chapter 10, "Active Directory Maintenance," for details.
Here is a checklist of domain-related services that the domain controller might be hosting:
Before demoting the bridgehead server for a site, you should assure yourself that another server is available for inter-site replication. The Inter-Site Topology Generator (ISTG) is responsible for determining the bridgehead server. If you down the ISTG, the remaining servers will realize after an hour that it is not available and they will determine which domain controller will become the new ISTG. See Chapter 7, "Managing Active Directory Replication," for details of the selection process. Determine the identity of the servers using the Replication Monitor, Replmon.
Before demoting a domain controller that is also an operations master, you should first transfer the roles to another server. Use Replmon to determine the identity of the FSMOs.
Before demoting a Global Catalog server, be sure that another GC server is available in the site. If you leave a site without a GC, the clients will be forced to go across the WAN and that will hurt performance. Use Replmon to determine the GCs in a forest.
Application naming contexts.
If you delete the last domain controller in a domain, you must decide what to do with the Application naming contexts that contain DNS resource records. If you have no further need for the DNS zones that have been integrated into Active Directory, you can elect to remove the naming contexts along with the domain. If you want retain the DNS zones, though, you must take steps to configure another DNS server and make it the primary master for the zones.
Windows 2000 and Windows Server 2003 DHCP servers that are members of a domain rely on Active Directory to determine their authorization status. If you demote all domain controllers, the server will continue to show an Authorized status and continue to pass out addresses. If you want the server to behave otherwise, you must either manually de-authorize it or stop the service completely.
To demote the domain controller, launch Dcpromo. It will sense that Active Directory is loaded and offer you the option of demoting the server. If this is the last server in the domain, be sure to check that option so that the server will take additional steps to clean out the last vestiges of the domain from the Registry and make the server a standalone server in a workgroup.
You can now restructure forests by renaming domains and changing the domain hierarchy. The forest functional level must be at Windows Server 2003. The utility that does this trick is called RENDOM. It is not installed by default. You can find it on the Windows Server 2003 CD under \Valueadd\Msft\Mgmt\Rendom.
You cannot use RENDOM to separate a domain into a separate forest, nor can you merge a domain with an existing forest, so it is not the true prune-and-graft that Microsoft promised for this release, but it goes a long way towards simplifying internal restructurings.
Renaming Domain Controllers
If the domain functional level is set to Windows Server 2003, you can rename a domain controller using a new switch on the NETDOM command in the Support Tools. There are two options.
Rename Using Alternate Name
This option uses NETDOM COMPUTERNAME to add an alternate name, make that name the primary name, and then remove the original name. The sequence of events is described in Procedure 9.6.
Procedure 9.6 Renaming a Domain Controller Using NETDOM COMPUTERNAME
From a command prompt at the console of the domain controller you want to rename, issue the following command to assign an alternate name to the server (be sure to enter the fully qualified DNS name, not just the flat name):
netdom computername <old-name> /add:<new-name>
Verify in DNS that the new name is registered.
Issue the following command to make the new name the primary name for the server:
netdom computername <old-name> /makeprimary:<new-name>
Restart the server so that the new name will take effect.
Following the restart, open a command prompt once again and issue the following command to remove the old name:
netdom computername <new-name> /remove<old-name>
Verify that the server now has only one name using the following command:
netdom computername <new-name> /enumerate
At this point, if you look in DNS or in the Properties window for the server, you'll see only the new name.
Rename by Replacing Primary Name
This option uses NETDOM RENAMECOMPUTER to replace the primary name of the domain controller in one swoop. You can also use the command to reboot the server with a few seconds delay (configured at the command line) so that the new primary name takes effect. The syntax is as follows:
netdom renamecomputer <old-name> /newname:<new-name> /reb: 1
Following restart, the server registers its new name with DNS, which will be its primary name in Active Directory.