Flexible Single Master Operations FSMO consists of 5 roles which are RID master, PDC emulator, Infrastructure master, Domain naming master, and Schema master.
These 5 unique roles are in most ways a holy grail of every Microsoft Windows Server administrator. If you find yourself unaware of these roles just know that most of your network weird unproductive activities could be well coded there
Operation Master Roles or FSMO meaning Flexible Single Master Operations
FSMO Roles
Forest Roles
Schema Master | The schema master is forest-wide and there’s one for each forest. Remember the adprep /domainprep command. It worked because this role was operational.
Domain Naming| Crucial for upgrades and demotions. It must be online when domains and application partitions in a forest are added or removed.
Domain Roles
PDC Emulator | This role must be online and accessible 24/7 for password and user account updates. Its a default target for the domain group policy and some admin tools
RID Master | Must be online for newly promoted domain controllers to obtain a local RID pool thats required to advertise or when existing domain controllers have to update their current RID pool allocation.
Infrastructure Master | Responsible for cross-domain reference and phantoms from the global catalog.
How To Determine The Role Holders
Query where the current FSMO roles reside with the following command
