1) Make sure your hypervisor generates VM-Generation-ID.
2) Make sure your PDC FSMO runs on Windows 2012.
- BTW you cannot clone your PDF FSMO.
3) Prepare
- %Windows%\NTDS\DCCloneConfig.xml
- %Windows%\NTDS\CustomDCCloneAllowList.xml
- Remove any services from your DC that cannot be cloned.
- PS C:> Get ADDCCloningExcludedApplicationList
5) Shutdown your DC and remove any snapshots.
6) Copy .vhd create new VM using copied .vhd.
When it comes to Virtualizing your Domain Controller you need to understand the pitfalls of it, in case you are not following the above given steps. You might be inquisitive to know what happens say when we take a snapshot of a DC or say we clone a DC in Virtualized environments which doesn't support VM-Generation-ID and or the environment has Non Windows 2012 Active Directory Domain Controllers.
Below are the three things which are going to help you understand why Snapshot or cloning of a DC is not a good idea when VM-Generation-ID aware virtualization platform is not used along with Windows 2012 DCs.
1) First understand what role is played by USN in AD replications.
2) Watch the excellent demo on "Active Directory Virtualization safeguards and Cloning with Windows Server 2012".
3) Then you must read this article which has some great details around Domain Controller Virtualization in HyperV environment. With a bit more of extra work you may be able to adapt this to VMWARE or Citrix virtualization platforms.