HP UX Red Hat Direry Server Software manual Solving Naming Conflicts

Solving Naming Conflicts

the conflicting changes need to be resolved. Mostly, resolution occurs automatically, based on the timestamp associated with the change on each server. The most recent change takes precedence.

However, there are some cases where change conflicts require manual intervention in order to reach a resolution. Entries that have a change conflict that cannot be resolved automatically by the replication process contain a conflict marker attribute nsds5ReplConflict. The nsds5ReplConflict attribute is an operational attribute which is indexed for presence and equality, so it is simple to search for entries that contain this attribute. For example:

ldapsearch -D adminDN -w password

-b "dc=example,dc=com" "nsds5ReplConflict=*" \* nsds5ReplConflict

The nsds5ReplConflict attribute is already indexed for presence and equality, but for performance reasons, if there are many conflicting entries every day, index the nsds5ReplConflict attribute in other indexes. For information on indexing, see Chapter 10, Managing Indexes.

This section contains the procedures for the following conflict resolution procedures:

•Section 18.1, “Solving Naming Conflicts”

•Section 18.2, “Solving Orphan Entry Conflicts”

•Section 18.3, “Solving Potential Interoperability Problems”

18.1. Solving Naming Conflicts

When two entries are created with the same DN on different servers, the automatic conflict resolution procedure during replication renames the last entry created, including the entry's unique identifier in the DN. Every directory entry includes a unique identifier given by the operational attribute nsuniqueid. When a naming conflict occurs, this unique ID is appended to the non-unique DN.

For example, the entry uid=adamss,ou=people,dc=example,dc=com is created on server A at time t1 and on server B at time t2, where t2 is greater (or later) than t1. After replication, server A and server B both hold the following entries:

•uid=adamss,ou=people,dc=example,dc=com (created at time t1)

•nsuniqueid=66446001-1dd211b2+uid=adamss,dc=example,dc=com (created at time t2)

The second entry needs to be renamed in such a way that it has a unique DN. The renaming procedure depends on whether the naming attribute is single-valued or multi-valued.

18.1.1. Renaming an Entry with a Multi-Valued Naming Attribute

343