Chapter 8. Managing Replication

of Directory Server. Compatibility is provided through two Directory Server plug-ins:

Legacy Replication Plug-in.The Legacy Replication Plug-in makes a Directory Server 8.0 instance behave as a 4.x Directory Server in a consumer role. For information on how to implement legacy replication using this plug-in, see Section 15, “Replication with Earlier Releases”.

Retro Changelog Plug-in.The Retro Changelog Plug-in can be used for a Directory Server supplier to maintain a 4.x-style changelog. This is sometimes necessary for legacy applications that have a dependency on the Directory Server 4.x changelog format because they read information from the changelog. For more information on the Retro Changelog Plug-in, see Section 16, “Using the Retro Changelog Plug-in”.

2. Replication Scenarios

This section describes the most commonly used replication scenarios:

Section 2.1, “Single-Master Replication”

Section 2.2, “Multi-Master Replication”

Section 2.3, “Cascading Replication”

These basic strategies can be combined in a variety of ways to create the best replication environment.

NOTE

Whatever replication scenario is implemented, consider schema replication. To avoid conflict resolution loops, the Referential Integrity Plug-in should only be enabled on one supplier replica in a multi-master replication environment. The plug-in is off by default.

2.1. Single-Master Replication

In the simplest replication scenario, the master copy of directory data is held in a single read-write replica on one server called the supplier server. The supplier server also maintains changelog for this replica. On another server, called the consumer server, there can be multiple read-only replicas. Such scenarios are called single-master configurations. Figure 8.1, “Single-Master Replication” shows an example of single-master replication.

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HP UX Red Hat Direry Server Software manual Replication Scenarios, Single-Master Replication