12.6 Maintaining the Schema

The schema is a system of rules and definitions for object attributes that establishes the content and format of each object and the object’s relationships in the database.

The Schema Maintenance Wizard contains several schema operations that might be necessary to bring an eDirectory server’s schema into compliance with the master of [Root]. However, these operations should be used only when necessary. The local and unattended repair operations already verify the schema.

For more information on the eDirectory schema, see Section 5.0, Managing the Schema.

Use the Schema Maintenance Wizard to perform the following operations:

12.6.1 Requesting Schema from the Tree

Use this operation to request the master replica of the root of the tree to synchronize its schema to this server. Any changes to the schema will be propagated to this server from the master replica of the [Root] for the next 24 hours.

IMPORTANT:If all servers request the schema from the master replica, network traffic can increase. Therefore, use this option with caution.

  1. In iManager, click the Roles and Tasks button Roles and Tasks button.

  2. Click eDirectory Maintenance > Schema Maintenance.

  3. Specify the server that will perform the operation, then click Next.

  4. Specify a user name, password, and context for the server where you will perform the operation, then click Next.

  5. Click Request Schema from Tree, then click Next.

  6. Follow the online instructions to complete the operation.

12.6.2 Resetting the Local Schema

This operation invokes a schema reset which clears the time stamps on the local schema and requests an inbound schema synchronization.

This operation is unavailable if executed from the master replica of the [Root] partition. This is to ensure that not all servers in the tree reset at once.

  1. In iManager, click the Roles and Tasks button Roles and Tasks button.

  2. Click eDirectory Maintenance > Schema Maintenance.

  3. Specify the server that will perform the operation, then click Next.

  4. Specify a user name, password, and context for the server where you will perform the operation, then click Next.

  5. Click Reset Local Schema, then click Next.

  6. Follow the online instructions to complete the operation.

12.6.3 Performing Optional Schema Enhancements

This operation extends and modifies the schema for containment and other schema enhancements.

This operation requires that this server contain a replica of the [Root] partition and that the state of the replica must be On.

Previous versions of eDirectory cannot synchronize these changes.

  1. In iManager, click the Roles and Tasks button Roles and Tasks button.

  2. Click eDirectory Maintenance > Schema Maintenance.

  3. Specify the server that will perform the operation, then click Next.

  4. Specify a user name, password, and context for the server where you will perform the operation, then click Next.

  5. Click Optional Schema Enhancements, then click Next.

  6. Follow the online instructions to complete the operation.

12.6.4 Importing Remote Schema

This operation lets you select an eDirectory tree that contains the schema you want to add to the current tree’s schema.

After you select a tree, the server that holds the master replica of the [Root] partition is contacted. The schema from that server is used to extend the schema on the current tree.

In order to merge two trees, you might need to import the schema from one tree to the other more than once. See Section 10.0, Merging NetIQ eDirectory Trees for more information.

  1. In iManager, click the Roles and Tasks button Roles and Tasks button.

  2. Click eDirectory Maintenance > Schema Maintenance.

  3. Specify the server that will perform the operation, then click Next.

  4. Specify a user name, password, and context for the server where you will perform the operation, then click Next.

  5. Click Import Remote Schema, then click Next.

  6. Follow the online instructions to complete the operation.

12.6.5 Declaring a New Schema Epoch

An epoch is an instant in time that is arbitrarily selected as a point of reference. It is synonymous with era or new version. Epochs control the synchronization of replicas. When a new epoch is declared, it begins on the master replica. Other replicas cannot send updates to a replica with a newer epoch, but they receive updates from it until they become fully synchronized with it.

When other replicas of a given partition are synchronized with the updated replica, meaning that each replica’s epoch is the same, bidirectional synchronization is allowed again.

When you declare a new schema epoch, the master replica of the [Root] partition is contacted and illegal time stamps are repaired on the schema records. A new epoch for the schema is then declared on that server, but it affects the entire tree.

All other servers receive a new copy of the schema including the repaired time stamps.

If the receiving server contains a schema that was not in the new epoch, objects and attributes that use the old schema are changed to the Unknown object class or attribute.

IMPORTANT:Do not perform this operation unless instructed to do so by NetIQ Support.

  1. In iManager, click the Roles and Tasks button Roles and Tasks button.

  2. Click eDirectory Maintenance > Schema Maintenance.

  3. Specify the server that will perform the operation, then click Next.

  4. Specify a user name, password, and context for the server where you will perform the operation, then click Next.

  5. Click Declare a New Epoch, then click Next.

  6. Follow the online instructions to complete the operation.