Configuring alias dereferencing in a Directory Assistance document for a remote LDAP directory

An alias entry in an LDAP directory is an entry that points to another entry. Searching the entry that an alias entry points to is known as dereferencing an alias.

About this task

Dereferencing aliases can cause poor search performance for some LDAP directories. Select one of the following options in the Dereference alias on search field in a Directory Assistance document for an LDAP directory to control the extent to which alias dereferencing occurs when searching the remote LDAP directory.

Table 1. Dereference alias on search options

Option

Description

Never

Never dereference alias entries. If there are no alias entries in the LDAP directory that require dereferencing, choose this option to improve search performance.

Only for subordinate entries

Dereference alias entries subordinate to a specified search base, but do not dereference an alias search base entry.

Only for search base entries

Deference an alias entry for a specified search base, but do not dereference alias entries subordinate to the search base.

Always

Always dereference aliases. This selection is the default behavior.

Example of alias dereferencing

Suppose an LDAP directory has these entries:

o=Renovations1

o=Renovations2 (alias entry that points to o=Renovations1)

cn=John Doe, o=Renovations1

cn=John Doe, o=Renovations2 (alias entry that points to cn=John Doe, o=Renovations1)

The following table describes which of these entries are returned for a subtree search of o=Renovations 2 (o=Renovations2 and subordinate entries) for each Dereference alias on search option.

Table 2. Dereference alias on search option results

Option

Entries returned

Never

o=Renovations2

cn=John Doe, o=Renovations2

Only for subordinate entries

o=Renovations2

cn=John Doe, o=Renovations1

Only for search base entries

o=Renovations1

cn=John Doe, o=Renovations2

Always

o=Renovations1

cn=John Doe, o=Renovations1