Migrating Domain Controllers
Applies To: Windows Server 2008, Windows Server 2008 R2, Windows Server 2012, Windows Server 2012 R2
Applies to: Active Directory Migration Tool 3.2 (ADMT 3.2)
In Active Directory or Active Directory Domain Services (AD DS), you can migrate domain controllers between domains. To do this, you must perform the following actions:
Remove Active Directory or AD DS from the domain controller.
Migrate the domain controller as a member server to the target domain.
Reinstall Active Directory or AD DS.
If the server is running a version of Windows Server that is lower than the functional level of the target domain, you must upgrade the server to a newer version of Windows Server before installing AD DS or maintain it as a member server in the target domain.
The same steps are required to migrate an RODC as are required for a writeable domain controller.