How it works...

In Windows Server 2012 (and later versions), the whole Active Directory preparation process is automated. When you promote a Windows Server 2012-based member server (or any newer version of Windows Server) to an additional domain controller for a domain, or upgrade a domain controller running a previous version to Windows Server 2012 (or any newer version of Windows Server), the Active Directory Domain Services Configuration Wizard determines whether the environment needs to be prepared as part of the promotion process.

Larger organizations often separate the schema or preparation work from the actual domain controller-promotion process work to minimize risk, adhere to small change windows, and more.

However, adprep.exe is still available to prepare the Active Directory forest and/or Active Directory domain(s) manually.