Windows Server 2012 HYPER-V has a great feature that to be honest until few months ago i didn't know it. he feature is the Domain Controller Clone. As IT Pro you must know that to restore a Doain Controller it's not so simple. It's not only a Restore from a Backup. You must have prepare a Paln with specific tests to Restore successfull a failed Domain Controller.
With a simple words everything else as restore , copy , snapshot except rebuilding from scratch it has the potential to create more problems in the directory.