A global catalog server is a domain controller. It is a master searchable database that CONTAINSINFORMATION about every OBJECT in every domain in a forest. The global catalog CONTAINS acomplete replica of all objects in Active Directory for its host domain, and contains a partialreplica of all objects in Active Directory for every other domain in the forest.It has two IMPORTANT functions:Provides group membership information during logon and authenticationHelps users locate resources in Active Directory

A global catalog server is a domain controller. It is a master searchable database that containsinformation about every object in every domain in a forest. The global catalog contains acomplete replica of all objects in Active Directory for its host domain, and contains a partialreplica of all objects in Active Directory for every other domain in the forest.It has two important functions:Provides group membership information during logon and authenticationHelps users locate resources in Active Directory