About Knowledge References - Red Hat DIRECTORY SERVER 8.1 - DEPLOYMENT Deployment Manual

Figure 5.6. Directory Tree with Multiple Root Suffixes
The dc=example, dc=com entry represents a root suffix. The entry for each hosted ISP is also a
root suffix (o=example_a and o=example_b). The ou=people and the ou=groups branches are
subsuffixes under each root suffix.

5.3. About Knowledge References

After distributing the data over several databases, define the relationship between the distributed
data using knowledge references, pointers to directory information held in different databases. The
Directory Server provides the following types of knowledge references to help link the distributed data
into a single directory tree:
• Referrals — The server returns a piece of information to the client application indicating that the
client application needs to contact another server to fulfill the request.
• Chaining — The server contacts other servers on behalf of the client application and returns the
combined results to the client application when the operation is finished.
The following sections describe and compare these two types of knowledge references in more detail.
5.3.1. Using Referrals
A referral is a piece of information returned by a server that informs 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:
• Default referrals — 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. One default referral can be set for the Directory Server and a separate default
referral for each database.
About Knowledge References
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