Active Directory supports multimaster replication of the directory data store between all domain controllers (DC) in the domain, so all domain controllers in a domain are essentially peers. However, some changes are impractical to perform in using multimaster replication, so, for each of these types of changes, one domain controller, called the operations master, accepts requests for such changes.
In every forest, there are at least five operations master roles that are assigned to one or more domain controllers. Forest-wide operations master roles must appear only once in every forest. Domain-wide operations master roles must appear once in every domain in the forest.
The Forest-wide operations master roles are :
- Schema Master ( controls all updates and modifications to the schema. There can be only one schema master in the entire forest. )
- Domain Naming Master (Â The domain controller holding the domain naming master role controls the addition or removal of domains in the forest. There can be only one domain naming master in the entire forest. )
The Domain-wide operations master roles are :
- Infrastructure Master (Â At any time, there can be only one domain controller acting as the infrastructure master in each domain. The infrastructure master is responsible for updating references from objects in its domain to objects in other domains. The infrastructure master compares its data with that of a global catalog. )
- Relative ID (RID) Master ( The RID master allocates sequences of relative IDs (RIDs) to each of the various domain controllers in its domain. At any time, there can be only one domain controller acting as the RID master in each domain in the forest. )
- Primary domain controller (PDC) emulator Master (Â The PDC emulator master processes password changes from client computers and replicates these updates to all domain controllers throughout the domain. At any time, there can be only one domain controller acting as the PDC emulator master in each domain in the forest. )
To get the list of all FSMO Roles using  command line tool, run the following command:
- Netdom /Query FSMO
To get the list of individual FSMO Roles using  command line tool, run the following commands :
- DSQuery server –hasfsmo –pdc
- DSQuery server –hasfsmo –infr
- DSQuery server –hasfsmo –rid
- DSQuery server –hasfsmo –name
- DSQuery server –hasfsmo –schema