A global catalog is an Active Directory directory service that contains a partial replica of every object in all domains in the forest. This allows users to search for objects in any domain in the forest, even if they do not have access to that domain. To check if a server is a global catalog, you can use the following steps:
The global catalog was introduced in Windows 2000 and has been a key part of Active Directory ever since. It provides a number of important benefits, including: