Multiple Group Policy Objects

Each non-local Group Policy object is stored in a specific domain, which we can call the storage domain. The storage domain should not be confused with a domain to which the Group Policy object is linked.

You can link multiple Group Policy objects to a single site, domain, or organizational unit. However, many sites, domains, and organizational units, can all obtain policy from a single Group Policy object by way of links to it, regardless of which domain the Group Policy object is stored in.

A Group Policy object can be linked to its storage domain, and if network connections to other domains are slow this is desirable. However, it doesn't have to be linked to its storage domain.

It is also possible to link a single Group Policy object more than once to a single site, domain, or organizational unit, though it is seldom useful to do so.

For performance reasons, it is best to avoid linking to a Group Policy object in a different domain.