Sun Directory Server Enterprise Edition 7.0 Deployment Planning Guide

Cascading Replication

In a cascading replication configuration, a server acting as a hub receives updates from a server acting as a supplier. The hub replays those updates to consumers. The following figure illustrates a cascading replication configuration.

Figure 11–5 Cascading Replication Configuration

Figure shows cascading replication.

Cascading replication is useful in the following scenarios:

The following figure shows cascading replication to a large number of consumers.

Figure 11–6 Cascading Replication to a Large Number of Consumers

Figure shows cascading replication to a large number
of consumers with replication traffic through several hubs..

In Figure 11–6, hubs 1 and 2 relay replication updates to consumers 1 through 10, leaving the master replicas with more resources to process directory updates.

The masters and the hubs maintain a change log. However, only the masters can process directory modification requests from clients. The hubs contains a Replication Manager entry for each master that sends updates to them. Consumers 1 through 10 contain Replication Manager entries for hubs 1 and 2.

The consumers and hubs can process search requests received from clients, but cannot process modification requests. The consumers and hubs refer modification requests to the masters.