What Does Flexible Single-Master Operation (FSMO) Mean?
Flexible single master operation (FSMO) is a Microsoft Active Directory feature that is a specialized domain controller task used when standard data transfer and update methods are inadequate. Tasks that do not suit multimaster replication are only viable as flexible single-master operations.
Techopedia Explains Flexible Single-Master Operation (FSMO)
Domain controllers can hold one or more FSMO roles. These are functionalities related to the Windows 2000 Active directory service, which is unique within the domain. There are two forest-wide FSMO roles and three domain-wide FSMO roles. The number of FSMO roles in a forest depends on the number of domains in that forest. The forest-wide FSMO roles are schema master and domain naming master.
