TABLE OF CONTENTS Active Directory uses the Global Catalog (GC), which is a copy of all the Active Directory objects in the forest, to let users search for directory information across all the domains in the forest. The GC is also used to resolve user principal names (UPNs) when the domain controller (DC) that is authenticating logon isn t aware of the account (because that account resides in a different domain). When the DC can t find the user s account in its own domain database, it then looks in the GC. The GC also stores information about membership in Universal Groups.
Because the GC performs all these functions for the multidomain network, it is important for administrators to understand how it works and how to create, manage, and place the GC servers that hold the GC. In this chapter, we look at this special type of DC: the GC server. You ll learn about the role the GC plays in the network, and how to customize the GC using the Schema Microsoft Management Console (MMC) snap-in. We show you how to create and manage GC servers, and explain how GC replication works. You ll learn about the factors to consider when placing GC servers within sites.
Next, we address the Active Directory schema itself. You ll learn about schema components: classes and attributes, and the naming of schema objects. We show you how to install and use the Schema management console, and you ll learn how to extend the schema and how to deactivate schema objects.
