Exit Print View

Sun OpenDS Standard Edition 2.0 Architectural Reference

Get PDF Book Print View

Document Information

The Directory Server Access Control Model

Understanding the Directory Server Schema

Index Databases

Understanding Directory Server Plug-Ins

Directory Server Replication

Overview of the Directory Server Replication Architecture

Basic Replication Architecture

Replication Servers

Replication Change Numbers

Replication Server State

Operation Dependencies

How Replication Works

Directory Server Change Processing

Change Replay

Auto Repair

Directory Server Crashes

Replication Server Crashes

Historical Information and Conflict Resolution

What is a Replication Conflict?

Resolving Modify Conflicts

Resolving Naming Conflicts

Purging Historical Information

Schema Replication

Schema Replication Architecture

Replication Status

Replication Status Definitions

Degraded Status

Full Update Status and Bad Generation ID Status

Replication Groups

Replication Server Selection

Replication Groups in a Multi-Data Center Deployment

Assured Replication

Assured Replication Modes

Safe Data Mode

Safe Read Mode

Safe Read Mode and Replication Groups

Assured Replication Connection Algorithm

Assured Replication and Replication Status

Assured Replication Monitoring

Root Users and the Privilege Subsystem

Supported Controls and Operations

Assured Replication and Replication Status

When a replication server detects that a directory server is out of sync regarding the overall updates made in the topology, that directory server is said to have a degraded status. A directory server that is out of sync is unlikely to be able to send the expected acknowledgments in time for the replication server to avoid a timeout situation. The server therefore has a degraded status until it has an acceptable level of updates. With a degraded status, a directory server is no longer expected to send acknowledgments to the replication server, until it returns to having a normal status.

Because a directory server with a degraded status is unable to send acknowledgments, the synchronization of an LDAP operation in safe read mode cannot be assured. In other words, data read from this directory server might not contain the modifications made on another directory server in the topology.

For more information, see Replication Status Definitions.