Red Hat Directory Server 8.0 Administrator's Guide

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.
Chapter 8. Managing Replication
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