Managing Partitions and Replicas

Partitions are logical divisions of the NDS® database that form a distinct unit of data in the NDS tree that administrators use to store and replicate NDS information. Each partition consists of a container object, all objects contained in it, and the information about those objects. Partitions do not include any information about the file system or the directories and files contained there.

Instead of storing a copy of the entire NDS database on each server, you can make a copy of the NDS partition and store it on many servers across the network. Each copy of the partition is known as a replica. You can create any number of replicas for each NDS partition and store them on any server. The types of replicas include master, read/write, read only, subordinate references, filtered read/write, and filtered read only.

Table 28 describes the replica types.


Table 28. Replica Types

Replicas Description

Master, read/write, and read only replicas

Contain all objects and attributes for a particular partition.

Subordinate references

Used for tree connectivity.

Filtered replicas

Contain a subset of information from the entire partition, consisting of only the desired classes and attributes. Desired classes and attributes are defined by the server's replication filter, which is used to identify which classes and attributes are allowed to pass during inbound synchronization and local changes.

Filtered replicas allow administrators to create sparse and fractional replicas.

  • Sparse replicas: Contain only the object classes that you specify
  • Fractional replicas: Contain only the attributes you specify.

The functionality of filtered replicas enables fast response when the data stored in NDS eDirectory is procured by applications. Filtered replicas also allow more replicas to be stored on a single server.

Read/write filtered replicas

Allow local modifications to classes and attributes that are a subset of the server's replication filter. However, these replicas can only create objects if all mandatory attributes for the class are within the replication filter.

Read only filtered replicas

These replicas do not allow local modifications.

This section describes how to manage partitions and replicas.