Partitions – logical sections of the NDS database that are managed by admin users. You can break large databases up so they are on different servers for efficient management.
Replicas – copy of all the data stored on a server within the boundary of the partition. Replicas are hidden files stored on the SYS: volume. Four types; Master, Read/Write, Read-only, Subordinate Reference.
§ § Master – complete copy of a partition that is used s the source for all other replica copies of that partition. Only one master per partition. Only replica that can be used to manage partitions (can create, split, or move partitions), authenticates users, can generate and propagate object changes to the other replicas.
§ § Read/Write – Most common type, can be promoted to a master is the server holding the master is downed, can authenticate users, can generate changes to update other replicas of that partition.
§ § Read-only – has little use (not recommended), permit users to view or search for object information, can’t provide authentication, don’t generate changes to other replicas, must pass on login requests to the master replica for user logins.
§ § Subordinate references – pointers to replicas of other types, created and maintained by NDS to facilitate NDS tree navigation
Viewing replicas – use NDS manager from win32 directory. Windows can be set up like in NWADMIN32.EXE to show two servers and to set context. It displays information about the replicas.