Using Referrals; The Structure Of An Ldap Referral - Red Hat DIRECTORY SERVER 7.1 - DEPLOYMENT Deployment Manual

Using Referrals

A referral is a piece of information returned by a server that tells a client
application which server to contact to proceed with an operation request. This
redirection mechanism occurs when a client application requests a directory entry
that does not exist on the local server.
Directory Server supports two types of referrals:
• A default referral — The directory returns a default referral when a client
application presents a DN for which the server does not have a matching
suffix. Default referrals are stored in the configuration file of the server. You
can set a default referral for the Directory Server and a separate default referral
for each database.
The default referral you set for each database is done through the suffix
configuration information. When the suffix of the database is disabled, you can
configure the directory to return a default referral to client requests made to
that suffix. For more information about suffixes, refer to "About Suffixes," on
page 94. For information on configuring suffixes, refer to Red Hat Directory
Server Administrator's Guide.
• Smart referrals — Smart referrals are stored on entries within the directory
itself. Smart referrals point to Directory Servers that have knowledge of the
subtree whose DN matches the DN of the entry containing the smart referral.
All referrals are returned in the format of an LDAP uniform resource locator (URL).
The following sections describe the structure of an LDAP referral, and then
describe the two referral types supported by Directory Server.

The Structure of an LDAP Referral

An LDAP referral contains information in the format of an LDAP URL. An LDAP
URL contains the following information:
• The hostname of the server to contact.
• The port number of the server.
• The base DN (for search operations) or target DN (for add, delete, and modify
operations).
For example, a client application searches
surname . A referral returns the following LDAP URL to the client
Jensen
application:
ldap://europe.example.com:389/ou=people,l=europe,dc=example,dc=c
om
dc=example,dc=com
Chapter 5 Designing the Directory Topology
About Knowledge References
for entries with a
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