c# print barcode zebra printer Configuring Sites and Managing Replication in C#.NET

Create Quick Response Code in C#.NET Configuring Sites and Managing Replication

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After you have configured sites and site links, the KCC automatically designates a domain controller in each site, for each intersite transport, as the bridgehead server. A bridgehead server is a single domain controller in a site, the contact point, used for rep lication between sites. The KCC automatically creates connection objects between bridgehead servers. When a bridgehead server receives replication updates from another site, it replicates the data to the other domain controllers within its site. A bridgehead server is designated automatically by the KCC. You can also specify a preferred bridgehead server if you have a computer with appropriate bandwidth to transmit and receive information. If you specify a preferred bridgehead server rather than use the one designated by the KCC, you can select the optimum conditions for the connection between sites. You can specify multiple preferred bridgehead servers, but only one is active at any time in a single site.

By specifying preferred bridgehead servers, you limit the ability of the KCC to provide failover if the bridgehead servers you designated as preferred go offline. If an active pre ferred bridgehead server fails, Active Directory selects another preferred bridgehead server from the set you designated. If no other preferred bridgehead servers are specified or no other preferred bridgehead servers are available, replication does not occur to that site even if there are servers that can act as bridgehead servers.

The following steps, illustrated in Figure 5-2, show how intersite replication works: 1. At the interval determined by the selected replication frequency, the bridgehead server in the Zurich site polls the bridgehead server in the Lucerne site for any updated data. 2. If the bridgehead server in the Lucerne site finds that it has updated Active Direc tory data, it compresses the data (if larger than 50 KB) and sends it to the bridgehead server in the Zurich site. 3. When the bridgehead server in the Zurich site has received all of the data, it then replicates the data to the other domain controllers in the site, without compressing the information.

Note that polling and pull replication, rather than notification and push replication, are used between bridgehead servers during intersite replication. Pull replication is more efficient for intersite replication because the destination domain controller knows which replication data to request. In contrast, notification and push replication are more efficient for intrasite replication, when domain controllers are well connected and not restrained by site link schedules.

The following questions are intended to reinforce key information presented in this lesson. If you are unable to answer a question, review the lesson and then try the ques tion again. Answers to the questions can be found in the Questions and Answers sec tion at the end of this chapter. 1. What is a site

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2. Which directory partition replica type must be replicated to all domain controllers within the domain

5. Which of the following actions does not trigger replication a. Accessing an object b. Creating an object c. Deleting an object d. Modifying an object e. Moving an object

A site is a set of IP subnets connected by a highly reliable and fast link (usually a LAN). Site structure mirrors the location of user communities. Sites have two main roles: to facilitate authentication and the replication of data between sites. The replication process ensures that changes made to a replica on one domain controller are synchronized to replicas on all other domain controllers within the domain. Creating, modifying, moving, or deleting an object triggers replication between domain controllers. Active Directory replicates information in two ways: intrasite (within a site) and intersite (between sites). There are four types of directory partition replicas: schema, configuration, domain, and application. A site link is a logical, transitive connection between two or more sites that mirrors the network links and allows replication to occur. By default, all site links are tran sitive. A site link bridge connects two or more site links in a transport where tran sitivity has been disabled in order to create a transitive and logical link between two sites that do not have an explicit site link. A bridgehead server is a single domain controller in a site, the contact point, used for replication between sites, and is designated automatically by the KCC.