Active Directory migration from an older version to a newer one is a common challenge for any identity infrastructure. In some documentation, this is called Active Directory upgrades, but I prefer to call it Active Directory migration. In this process, a new AD DS version will be installed on a new server. Then, the FSMO roles will migrate to the new domain controllers.
Once this is completed, the older version of AD DS will be decommissioned. Afterward, the domain and forest function levels will be raised to match the new AD DS version. Even though each AD DS version has core functions that are the same, newer versions always have new features and enhancements that apply to the domain or forest level. Therefore, it's more of a migration than an upgrade. The migration term is also used for migrating Active Directory objects from one...
