Comparing AD Schemas

For an upcoming AD upgrade from Windows Server 2003 to Windows Server 2008 R2 I recommended to verify the procedure in a test lab. However, the customer was unsure which schema extensions he had deployed in his production environment.

You can setup a test lab AD forest and install the schema extension of the applications you are sure that have been deployed in your production AD forest, for example, Exchange Server 2007 or Office Communications Server 2007.

Now you can use the steps described in the TechNet Magazine article “Export, Compare, and Synchronize Active Directory Schemas” or in the Directory Services Team blog article “Determine Applied Schema Extensions with AD DS/LDS Schema Analyzer” to compare your production AD schema with the schema of your test lab using the AD DS/LDS Schema Analyzer.

This allows you to see which schema extension might be missing.