Understanding ADAM sites

  • Article

Applies To: Windows Server 2003 R2

Sites

Active Directory Application Mode (ADAM) uses topology information, which is stored as site objects and site link objects in the configuration directory partition, to build the most efficient replication topology for a configuration set. You can use sites in ADAM to represent the physical structure, or topology, of your network. You can use ADAM ADSI Edit to define site objects and site link objects.

Site objects

You can create a site object in ADAM to represent each area of your network (typically, a building or a group of buildings) in which all computers are connected by high-speed bandwidth. You can then move the directory objects of ADAM instances that are located in each area of the network into the corresponding site object. By default, the directory objects of each ADAM instance that you create belong to a single default site (CN=Default-First-Site-Name,CN=Sites,CN=Configuration,CN={GUID}).

For information about establishing single or multiple sites, see Administering sites.

You can use site link objects in the directory to represent low-speed bandwidth connections between the sites on your network. Site link objects help you tune replication on your network; you can use them to determine the relative cost of replication across each site link. By default, the default site (CN=Default-First-Site-Name) belongs to the default site link object (CN=DEFAULTIPSITELINK,CN=IP,CN=Inter-Site Transports,CN=Sites,CN=Configuration,CN={GUID} ). You can add new sites that you create to the default site link object. You can also create additional site link objects to represent each of the actual site links on your network.

Each site link object in the directory has an associated cost. You can edit the cost attribute on a site link object to specify the relative cost of replication across that site link. ADAM takes into consideration site link costs when it builds the replication topology. ADAM considers a site link with a higher cost to be less desirable than a site link with a lower cost. When multiple paths for replication are available, ADAM prefers the site link with the lower cost.

For more information about how sites affect replication, see Understanding ADAM sites and replication.