Active Directory : increase the functional level of the domain and the forest
The functional level of the domain and forest corresponds to the “version” of your Active Directory environment and allows access to more or fewer features depending on the level of each.
Mainly this level change occurs when upgrading to Windows when replacing / migrating domain controllers. The version change may also be necessary for the installation of new service like Exchange, ADFS …
Before making this change, it must be verified that your environment will support the functional level increase.
Example: If you want to upgrade from 2003 to 2012, all domain controllers should at least work with Windows Server 2012.
Here are some notable features brought up during version upgrades:
Replication of sysvol with DFS-R: Domain in 2008 level
ADMT: Active Directory Domain Migration Tool ADMT (Active Directory Migration Tool) is a free Microsoft tool that allows the migration of objects (Users, Computers, and Groups) between two Active Directory domains. Some examples of using ADMT: Enterprise merge to consolidate Active Directory. E