When thinking about Active Directory migration from Server 2003 to Server 2012 R2, it’s good to have a list of things to do and the order in which you should do them.
There is a series of blog posts in the “Ask Premier Field Engineering (PFE) Platforms” on upgrading or migrating Active Directory to Windows Server 2012 that you should consult to get more details on planning and making the transition:
The PFE blogs suggest that you do the following:
- Document your current deployment. This includes understanding the capacity and usage profile of your current domain controllers.
- Determine and document dependent applications. This includes figuring out which applications are dependent on AD and the nature of that dependency.
- Verify that changes made during the upgrade will not adversely influence any applications that have a dependency on AD
- Determine whether other services and applications are deployed on DCs. Though the general recommendation is that DCs should only be DCs, in many environments, applications, services, and roles end up deployed on DCs in an ad-hoc manner, only to become permanently deployed.
Once you’ve got a handle on everything you need to do, you’ll have an understanding of which issues you need to tackle first and which ones you can put off until later.