We need to upgrade the functionality of our domain. We are currently running 2k3 OS on the DCs. We have a two-tiered environment with our Schema master domain at the top of the forest and our production domain under it. The Operations masters for both domains are running in VMWare. Several remote sites have physical DCs running as Global Catalogs.
The current functional levels are:
Forest = Windows 2000
Domain = Windows 2000 Native
We need to switch the functional levels to:
Forest = Windows 2003 Native
Domain = Windows 2003 Native
Before we proceed with the simple task of pushing the "OK" button to perform the upgrade we need to establish an install / rollback plan.
From what I have read, Microsoft has indicated under our current configuration upgrading the forest mode from 2k to 2k3 native will also push the domain mode in all the domains in the forest up to 2k3 native mode .
We plan to "VM Snapshot" the operations masters prior to the upgrade. To rollback from the upgrade requires bringing up the operations masters from the snapshots and then demote all the other DCs, remove the metadata and repromote them.
Has anyone been through an install / rollback like this and can confirm the correctness of upgrade process and the rollback plan?
Any "gotchas" to look out for?