We've all heard how Windows 2000 Server and Windows Server 2003 can co-exist peacefully on the same network. While that is basically true, a few issues are often overlooked or pushed under the rug when this discussion takes place. One of the most significant issues is the schema version of the forest. A Windows Server 2003 domain controller can support a Windows 2000 Server schema, but you'll be missing out on many of the new and improved features of Windows Server 2003 Active Directory.
Fortunately, there is a simple way to upgrade or revise your forest schema before you perform the installation process to upgrade Windows 2000 Server domain controllers to Windows Server 2003 domain controllers. A tool named ADPREP (Active Directory Prep) is used to properly upgrade a forest's schema. This tool is found on the Windows Server 2003 distribution CD in the i386 folder. It can be run directly off of the CD, accessed through a network share or distributed on a floppy.
To upgrade a Windows 2000 Server forest's schema, you must run the ADPREP tool several times:
- First, all domain controllers in the forest must be Windows 2000 Server running Service Pack 1 with QFE 265089 or Service Pack 2 (or later). (Service Pack 3 or later is preferred.)
- Second, run ADPREP with the /forestprep command on the schema master of the root domain of the forest.
- Third, run ADPREP with the /domainprep command on the infrastructure master of each domain in the forest.
Once you've completed this task, then you can upgrade each domain controller to Windows Server 2003. Following this procedure will ensure that your migration will result in obtaining full access to Windows Server 2003 based Active Directory rather than being stuck with Windows 2000 Server Active Directory.
James Michael Stewart is a partner and researcher for ITinfopros, a technology-focused writing and training organization.
This was first published in September 2004