LDAP-UX Client Services B.04.15 Administrator's Guide

6.5 Schema Extension Utility
6.5.1 Overview
A directory schema is a collection of attribute type definitions, object class definitions and other
information supported by a directory server. Schema controls the type of data that can be stored
in a directory server. Although there are some recommended schemas that came originally from
the X.500 standards, mostly for representing individuals and organizations, there is no universal
schema standard in place for every possible application. Also, there is no standard method for
installing the schema definition on a directory server. To support a particular schema definition,
LDAP developers are required to manually create schema definition files in the specific format
tailored for each version of a supported directory server. They also have to create a custom install
program for each variety of directory servers.
To address these issues, LDAP-UX Client Services B.04.10 supports the schema extension utility.
This tool queries the current status of the LDAP schema on an LDAP directory server and extends
the LDAP server schema with new schema definitions. This tool allows creation of a schema
definition in a general format, that can be installed on a number of different directory servers
types (such as Netscape/Red Hat Directory Server, Windows Active Directory Server, etc…). A
user with valid directory server administration privileges can use this tool to query and extend
schema definitions stored in an XML schema definition file into the LDAP directory server.
6.5.1.1 The Benefits of the Schema Extension Tool
The schema extension tool provides the following benefits:
• Assists application developers to easily install their application schemas to the LDAP directory
server.
• Supports automated schema integration into the directory server environment.
• Extends the LDAP directory server schema with new schema definitions dynamically using
the schema extension tool, or stores schema extension instructions in the specified file (usually
in LDIF format) so the schema can be extended into the directory server manually.
• Reduces user effort in schema extension.
• Simplifies schema management.
6.5.2 How Does the Schema Extension Utility Work
The schema extension utility, /opt/ldapux/bin/ldapschema, automatically maps a custom
schema definition in a general purpose format to the schema definition format required by the
specific LDAP directory server. The Netscape/Red Hat Directory Server and Windows Active
Directory Server (ADS) are fully supported by the ldapschema tool.
The schema extension utility extends the LDAP directory server with new object classes and
attribute types specified in a schema definition file. This utility extends only object classes and
attribute types that are not yet defined in a Directory Server schema. No new matching rules or
syntaxes can be installed on a Directory Server using this tool. If any attribute types specified in
the new schema definition use matching rules or syntaxes that are not defined in the LDAP
directory server, the schema extension tool maps these attribute types using alternate matching
rules and syntaxes the directory server supports. If no alternate matching rule or syntax is found
on an LDAP directory server, the default substitute matching rule or syntax will be used instead.
See the “Mapping Unsupported Matching Rules and LDAP Syntaxes” (page 219) section for
details.
The schema definitions are stored in an XML format file. This allows you to specify a general
schema definition that can be extended on different types and versions of directory servers. See
the “Schema Definition File” (page 209), “Defining Attribute Types” (page 211) and “Defining
Object Classes” (page 213) sections for details.
202 Command and Tool Reference