Bridgehead Server and Global Catalog Server configuration

Enabling or disabling a Global Catalog (GC)

1. Click Start, point to Programs, point to Administrative Tools, and then click Active Directory Sites and Services.
2. Expand the console tree for Sites, and then double-click the domain controller you want to work with in the Server folder for your desired site:
o Active Directory Sites and Services
o Sites
o Site that contains the domain controller that is hosting the global catalog
o Servers
o Domain controller that is hosting a global catalog
3. Right-click NTDS Settings, and then click Properties.
4. Click to select the Global Catalog check box to make this computer a Global Catalog server, or click to clear the check box to remove the global catalog.

WARNING Global catalog servers are required for user logons in any domain that is running Windows 2000 in native mode or a later version. The servers also required for Exchange address lookups and for searching Active Directory. Most of the time, we recommend that you configure all domain controllers in the forest as global catalog servers. This configuration makes sure that sufficient global catalog servers exist to respond to logon requests and to Exchange address lookups.

Note Clients must have access to a global catalog to log on, so at least one global catalog in every site is optimum to receive the benefits of containing network traffic that is provided by using sites.

Designating a preferred bridgehead server

1. Click Start, point to Programs, point to Administrative Tools, and then click Active Directory Sites and Services.
2. In the console tree, right-click the domain controller that you want to make a preferred bridgehead server, and then click Properties:
o Active Directory Sites and Services
o Sites
o Site that contains the domain controller that you want to make a preferred bridgehead server
o Servers
o The domain controller that you want to make a preferred bridgehead server
3. Click the intersite transport or transports for which this computer will be a preferred bridgehead server, and then click Add.

Note We recommend that you do not configure preferred bridgehead servers unless you have a specific and compelling requirement to do this. If you configure preferred bridgehead servers, you limit the ability of the Active Directory Knowledge Consistency Checker (KCC) to automatically configure a fault-tolerant intersite replication topology. If the server or servers in the preferred bridgehead list for a particular site are offline or unavailable, the KCC will not select a new bridgehead server for that site until the list is cleared or until one or more of the preferred servers are brought back online. During the interim, that site will be orphaned with regard to Active Directory replication. Additionally, domain controllers in that site will not replicate changes with domain controllers in any other sites.

Moving a domain controller between sites

1. Click Start, point to Programs, point to Administrative Tools, and then click Active Directory Sites and Services.
2. In the console tree, right-click the domain controller that you want to move to a different site, and then click Move:
o Active Directory Sites and Services
o Sites
o Site that contains the domain controller you want to move
o Servers
o Domain controller to be moved
3. In the Move Server dialog box, click the site to which you want to move the domain controller.

Note You can use this procedure to move servers and domain controllers between sites.

Checking the replication topology
1. Click Start, point to Programs, point to Administrative Tools, and then click Active Directory Sites and Services.
2. In the console tree, double-click the server you want to use to check replication topology:
o Active Directory Sites and Services
o Sites
o Site that contains the domain controller whose replication topology you want to check
o Servers
o Server you want to use to check replication topology
3. Right-click NTDS Settings, point to All Tasks, and then click Check Replication Topology.

Note Active Directory runs a process that considers the cost of inter-site connections, checks if any previously-available domain controllers are no longer available, checks if new domain controllers have been added, and then uses this information to add or remove Connection objects to create an efficient replication topology. This process does not affect manually-created Connection objects.

Connecting to a forest

1. Click Start, point to Programs, point to Administrative Tools, and then click Active Directory Sites and Services.
2. Right-click Active Directory Sites and Services, and then click Connect to Forest.
3. In Root domain, type the root domain of the forest. This is the root domain of the first domain tree that was created in the forest.

Note Active Directory Sites and Services views a single forest. Change forests to view and configure Active Directory Sites and Services settings for the forest you want to view.

Connecting to a domain controller
1. Click Start, point to Programs, point to Administrative Tools, and then click Active Directory Sites and Services.
2. Right-click Active Directory Sites and Services, and then click Connect to Domain Controller.
3. In Domain, type the domain name, or click Browse to select from the list of available domains.

Note Active Directory Sites and Services views and configures a single copy of the directory data. Change the domain controller to select an alternate domain controller whose directory data Active Directory Sites and Services will read and modify.