cn=schema, the subtree containing the schema elements currently loaded in the server.

user_suffix, the suffix for the default user database created when the Directory Server is setup. The name of the suffix is defined by the user when the server is created; the name of the associated database is userRoot. The database can be populated with entries by importing an LDIF file at setup or entries can be added to it later.

The user_suffix suffix frequently has a dc naming convention, like dc=example,dc=com. Another common naming attribute is the o attribute, which is used for an entire organization, like o=example.com.

The default directory tree can be extended to add any data relevant to the directory installation. For more information about directory trees, see Chapter 4 “Designing the directory tree”.

Figure 1-2 Expanded directory tree for example corp.

1.3 Directory Server data storage

The database is the basic unit of storage, performance, replication, and indexing. All Directory Server operations (importing, exporting, backing up, restoring, and indexing entries) are performed on the database. Directory data are stored in an LDBM database. The LDBM database is implemented as a plug-in that is automatically installed with the directory and is enabled by default.

By default, Directory Server uses one backend database instance for a root suffix, and, by default, there are two databases, o=NetscapeRoot for configuration entries and userRoot for directory entries. A single database is sufficient to contain the directory tree. This database can manage millions of entries.

This database supports advanced methods of backing up and restoring data, in order to minimize risk to data.

NOTE:

For database files that are larger than 2 gigabytes, the file system must support large files. Use the vxfs file system and set the largefiles option to on.

Multiple databases can be used to support the whole Directory Server deployment. Information is distributed across the databases, allowing the server to hold more data than can be stored in a single database.

12 Introduction to directory services