HP-UX Directory Server 8.1 deployment guide

5.2.1 About using multiple databases
Directory Server stores data in LDBM databases. This a high-performance, disk-based database.
Each database consists of a set of large files that contain all the data assigned to it.
Different portions of the directory tree can be stored in different databases.
For example, Figure 5-1 “Storing suffix data in separate databases” shows three suffixes being
stored in three separate databases.
Figure 5-1 Storing suffix data in separate databases
When the directory tree is divided between a number of databases, these databases can then be
distributed across multiple servers. For example, if there are three databases, DB1, DB2, and
DB3, to contain the three suffixes of the directory tree, they can be stored on two servers, Server
A and Server B.
Figure 5-2 Dividing suffix databases between separate servers
Server A contains DB1 and DB2, and Server B contains DB3.
Distributing databases across multiple servers reduces the workload on each server. The directory
service can therefore be scaled to a much larger number of entries than would be possible with
a single server.
In addition, Directory Server supports adding databases dynamically, which means that new
databases can be added when the directory service needs them without taking the entire directory
service off-line.
60 Designing the directory topology