Fan-Out and Partial Replication

This section gives a more detailed look at fan-out and partial replication.

In fan-out replication, a consumer replicates data directly from a supplier. That consumer can then be a supplier to one or more other consumers.

Figure 24-12 and its accompanying text explain the fan-out replication process.

Figure 24-12 The Fan-Out Replication Process

Text description of the illustration oidag084.gif

As Figure 24-12 shows:

1. An LDAP client issues a directory modification request to the directory on the supplier node.

2. The Oracle directory server on the supplier node performs the required modification in the directory store and simultaneously updates the change log store.

3. The directory replication server on the consumer node retrieves changes from the directory server on the supplier node and applies them to the directory server on the consumer.

4. The directory server on the consumer does the following simultaneously:
   • It makes the required modification, replicating the change in its directory store

   • It generates a shadow change log object in its change log store. The objects in this change log store can, in turn, be propagated to other fan-out consumers.

   • It updates the value of the orcllastappliedchangenumber attribute in the replication agreement entry to correspond to the number of the last change from the supplier node that it has applied

     See Also: "Change Logs in Directory Replication" for more information about the orcllastappliedchangenumber attribute