Content Search

Custom Search

Thursday, September 1, 2011

Active Directory Replication Terminology - Part II

Automatic Site Coverage:
To ensure that clients can locate a domain controller in the nearest available site, domain controller advertises itself (registers a site-related SRV record in DNS) in any site that does not have a domain controller for that domain and for which its site has the lowest-cost connections. This functionality is commonly known as "automatic site coverage."

To disable automatic site coverage on a domain controller:

  1. Click Start, click Run, type regedit, and then click OK.
  2. Navigate to the following registry subkey:
  3. Click Edit, point to New, and then click DWORD Value.
  4. Type AutoSiteCoverage as the name of the new entry, and then press ENTER.
  5. Double-click the new AutoSiteCoverage registry entry.
  6. Under Value data, type 0 to disable automatic site coverage or type 1 to enable it.

Automatic Site Link Bridge
By default, all site links are bridged, or transitive. This allows any two sites that are not connected by an explicit site link to communicate directly, through a chain of intermediary site links and sites. One advantage to bridging all site links is that your network is easier to maintain because you do not need to create a site link to describe every possible path between pairs of sites.

Bridge All Site Link
The setting inside AD Sites and Services to enable or disable site link bridges. If you disable site link bridging and you are using File Replication Service (FRS) to replicate DFS replicas, which include the SYSVOL share, the DFS site-costing ability is also disabled.

To turn off automatic site link bridging for KCC operation without hampering the ability of DFS to use Intersite Messaging to calculate the cost matrix. This site option is set by running the command repadmin /siteoptions +W2K3_BRIDGES_REQUIRED. This option is applied to the NTDS Site Settings object (CN=NTDS Site Settings,CN=SiteName,CN=Sites,CN=Configuration,DC=ForestRootDomain). When this method is used to disable automatic site link bridging (as opposed to turning off Bridge all site links), default Intersite Messaging options enable the site-costing calculation to occur for DFS

Site Costed Referall,
Defining the SiteCostedReferrals Registry value on the domain controllers will alter the DFS referrals so that all local domain controllers are listed first, randomly ordered, then the “next best” site’s domain controllers, and then all others. The “next best” logic is based on site link costs where the lower cost is preferred.

No comments: