Change Log - Netscape DIRECTORY SERVER 6.2 - DEPLOYMENT Deployment Manual

Introduction to Replication
For any particular replica, the supplier server must:
• Respond to read requests and update requests from directory clients.
• Maintain state information and a change log for the replica.
• Initiate replication to consumer servers.
The supplier server is always responsible for recording the changes made to
the read-write replicas that it manages. So, the supplier server makes sure that
any changes are replicated to consumer servers.
A consumer server must:
• Respond to read requests.
• Refer update requests to a supplier server for the replica.
Any time a request to add, delete, or change an entry is received by a consumer
server, the request is referred to a supplier for the replica. The supplier server
performs the request, then replicates the change.
In the special case of cascading replication, the hub supplier must:
• Respond to read requests.
• Refer update requests to a supplier server for the replica.
• Initiate replication to consumer servers.
For more information on cascading replication, refer to "Cascading Replication,"
on page 117.

Change Log

Every supplier server maintains a change log. A change log is a record that
describes the modifications that have occurred on a replica. The supplier server
then replays these modifications on the replicas stored on consumer servers, or on
other masters in the case of multi-master replication.
When an entry is modified, a change record describing the LDAP operation that
was performed is recorded in the change log.
110 Netscape Directory Server Deployment Guide • December 2003