HP-UX Directory Server Administrator Guide HP-UX Directory Server Version 8.1 (5900-3098, May 2013)

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 “Using the Retro changelog
plug-in” (page 381).
8.2 Replication scenarios
This section describes the most commonly used replication scenarios:
• “Single-master replication” (page 320)
• “Multi-master replication” (page 321)
• “Cascading replication” (page 323)
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.
8.2.1 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 15 (page 321) shows an example
of single-master replication.
320 Managing Replication