Directory Replication Concepts, 3 of 12

Full and Partial Directory Replication

This section contains these topics:

Full Directory Replication

Full replication involves propagating the entire DIT to another node. This type of replication ensures the high availability of the entire directory. You can also use it to distribute operations on the entire directory among different nodes.

Full replication can be based on either Oracle9i Advanced Replication or LDAP.

Partial Directory Replication

Partial replication enables you to propagate one or more subtrees, rather than the entire DIT, to another node. Decentralizing a directory in this way enables you to balance the workload between servers and build a highly available distributed directory complete with fault tolerance and failover. Because it brings data closer to the client, partial replication reduces response time and improves performance. You can configure partial replication by using the Replication Environment Management Tool.

Partial replication is LDAP-based only. It does not use Oracle9i Advanced Replication.

Figure 24-1 shows an example of partial replication.

Figure 24-1 Example of Partial Replication

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In a partial replication scenario, one or more naming contexts, but not the entire directory, are replicated. For example, in Figure 24-1, Server 1 contains three naming contexts: A, B, and C. Naming contexts B and C are replicated to Server 2, but naming context A is not.

Table 24-1 compares the two types of replication.

Table 24-1 Comparison of Full and Partial Replication

Full Replication	Partial Replication
Propagates an entire directory to other nodes	Propagates just part of the directory--for example, one or more, but not all, naming contexts--to other nodes
Propagates to a limited number of nodes	Propagates to an unlimited number of nodes
In a multimaster environment, allows a consumer to receive changes from more than one supplier	In a single-master environment, allows a consumer to receive changes from only one supplier