It helps to manage Active Directory replication if you have a road map of how the domain controllers connect to each other and what information they exchange. In this section, we'll take a look at what Active Directory components get replicated, where the replication traffic goes, how that traffic is managed, and what happens when conflicting updates collide with each other.
Domain controllers are like hard-working parents. They can only give what they have. Each domain controller has at least three naming context replicas:
Configuration. All domain controllers in a forest have a read/write copy of this naming context.
Schema. All domain controllers in a forest have a read-only copy of this ...