I have some questions about updating our Active Directory Schema.

Right now We have 4 Domain Controllers across 3 sites. They are all running Windows Server 2003 with SP1. None of them are R2. They are all running old hardware and need to be replaced. I would like to replace them all with virtual machines. I tried to dcpromo a new VM running Server 2003 R2 and it told me to do the Schema update first. This is where I have some questions.

First: All of my current DC's have retail copies of Windows installed. All of the installation media that I have is OEM. Can I run the ADPrep utility from the OEM Media on a server with Retail Media installed?

Second: Can I run the Schema update from a SP1 DC or does it need to have SP2 installed? I don't mind doing all the updates on the current DC's but I since they will all be replaced, it seems kindof like a waste of time (there are 200+ updates per server.)

Last: I have read this question about Schema update safety, but I don't understand how you can backup and safely restore AD if the update goes wrong. Is the process to reboot each DC into AD Restore Mode and restore them one at a time if the update fails?

Thanks for all your help.


1) Schema updates are not related to licensing in any way, so, yes, you can run a schema update from ANY Windows installation media (probably excluding SBS, but that's a completely different product).

2) No, SP2 is not a prerequisite for this schema update.

3) No, in order to fully restore AD from a backup, you only need to restart a single DC in DSRM and perform an authoritative restore; then standard AD replication will take care of overwriting all other DC's copies of the directory database with the one you restored (that's why it's called "authoritative").

| improve this answer | |
  • +1, Adding to this: 1. You can use the newest schema you're licensed for; schema is forest wide (not per DC or Domain); and SBS uses the same schema as standard. 2. Older software will simply ignore any newer schema it doesn't know how to use; it doesn't cause problems. 3. The restore has to be done on the Schema Master; schema updates will not replicate from any other server. It's a very simple process and honestly I've never heard of it going wrong (when using ADPrep). – Chris S Jul 19 '10 at 18:22
  • @Chris, I was wondering if SBS contains ADPrep at all, since it's supposed to be used as the only domain controller in its own domain and forest... I think a scenario where you would add a SBS DC to an existing, earlier forest (thus needing a schema update) would be quite unlikely. – Massimo Jul 19 '10 at 18:29
  • you can upgrade from older versions of SBS to newer, it comes with ADPrep. But you are correct that you can not add SBS to and existing domain/forest, you can only do an upgrade. – Chris S Jul 19 '10 at 18:40

The procedure is explained here: http://technet.microsoft.com/en-us/library/cc773360%28WS.10%29.aspx

You simply use adprep from the Win2003R2 CD (disk 2) and run it in your existing environment. You need to do this before you promote your first Win2003R2 Domain Controller.

| improve this answer | |

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.