Red Hat DIRECTORY SERVER 7.1 - DEPLOYMENT Deployment Manual page 105

In the illustration above, the client application performs the following steps:
The client application first binds with server A.
1.
Server A contains an entry for the client that provides a user name and
2.
password, so it returns a bind acceptance message. In order for the referral to
work, the client entry must be present on server A.
The client application sends the operation request to server A.
3.
However, server A does not contain the information requested. Instead, server
4.
A returns a referral to the client application telling them to contact server B.
The client application then sends a bind request to server B. To bind
5.
successfully, server B must also contain an entry for the client application.
The bind is successful, and the client application can now resubmit its search
6.
operation to Server B.
This approach requires server B to have a replicated copy of the client's entry from
server A.
Chaining solves this problem. A search request would occur as follows on a
chained system:
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