HP-UX Directory Server 8.1 deployment guide

3.4.5 Strategies for defining new attributes
For both application compatibility and long-term maintenance, try to use standard attributes
whenever possible. Search the attributes that already exist in the default directory schema and
use them in association with a new object class or check out the Directory Server Schema Guide.
However, if the standard schema does not contain all the information you need, then add new
attributes and new object classes.
For example, a person entry may need more attributes than the person,
organizationalPerson, or inetOrgPerson object classes support by default. As an example,
no attribute exists within the standard Directory Server schema to store birth dates. A new
attribute, dateOfBirth, can be created and set as an allowed attribute within a new auxiliary
object class, examplePerson.
attributetypes: ( dateofbirth-oid NAME 'dateofbirth' DESC 'For employee
birthdays'
SYNTAX 1.3.6.1.4.1.1466.115.121.1.15 X-ORIGIN 'Example defined')
objectclasses: ( 2.16.840.1.117370.999.1.2.3 NAME 'examplePerson' DESC
'Example Person Object Class'
SUP inetorgPerson MAY (exampleDateOfBirth $ cn) X-ORIGIN 'Example
defined')
NOTE: Never add or delete custom attributes to standard schema elements. If the directory
requires custom attributes, add custom object classes to contain them.
3.4.6 Deleting schema elements
Do not delete the schema elements included by default with Directory Server. Unused schema
elements represent no operational or administrative overhead. Deleting parts of the standard
LDAP schema can cause compatibility problems with future installations of Directory Server
and other directory-enabled applications.
However, unused custom schema elements can be deleted. Before removing the object class
definitions from the schema, modify each entry using the object class. Removing the definition
first might prevent the entries that use the object class from being modified later. Schema checks
on modified entries also fails unless the unknown object class values are removed from the entry.
3.4.7 Creating custom schema files
Administrators can create custom schema files for the Directory Server to use, in addition to the
99user.ldif file provided with Directory Server. These schema files hold new, custom attributes
and object classes that are specific to the organization. The new schema files should be located
in the schema directory, /etc/opt/dirsrv/schema.
All standard attributes and object classes are loaded only after custom schema elements have
been loaded.
34 Designing the directory schema