Using Chaining - Netscape DIRECTORY SERVER 6.01 - DEPLOYMENT Deployment Manual

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• Consider the security implications.
Access control does not cross referral boundaries. Even if the server where the
request originated allows access to an entry, when a smart referral sends a
client request to another server, the client application may not be allowed
access.
Also, the client credentials need to be available on the server to which the client
is referred for client authentication to take place.

Using Chaining

Chaining is a method for relaying requests to another server. This method is
implemented through database links. A database link, as described in the section
titled "Distributing Your Data," on page 78, contains no data. Instead, it redirects
client application requests to remote servers that contain the data.
During chaining, a server receives a request from a client application for data it
does not contain. Using the database link, the server then contacts other servers on
behalf of the client application and returns the results to the client application. This
operation is illustrated in the following diagram.
Each database link is associated to a remote server holding data. You can also
configure alternate remote servers containing replicas of the data for the database
link to use when there is a failure. For more information on configuring database
links, refer to the Netscape Directory Server Administrator's Guide.
Database links provide the following features:
• Invisible access to remote data.
Because the database link takes care of client requests, data distribution is
completely hidden from the client.
88 Netscape Directory Server Deployment Guide • January 2002