Configuring Active Directory Sites & Services is an important, but sometimes mishandled, part of administering a domain. The information in Sites & Services is used by AD to create a replication topology, determine which DCs should authenticate clients, and help users connect to applications and services. Sites & Services being misconfigured can result in increased logon times, poor user experience with some applications, or worse - a tombstoned DC if issues go undetected for too long. Here, we'll review what the information in Sites & Services is used for, the correct way to set it up, and how to verify that it is configured correctly.
by Mitchell Grande