Sun Directory Server Enterprise Edition 7.0 Reference

Client Affinity

Client affinity is defined between a client connection and a data source. When client affinity is defined, requests from a specified client connection are distributed to a specified data source in a data source pool.

The client affinity feature reduces the risk of propagation delay in deployments that use load balancing. Propagation delays can occur when a client makes consecutive requests that target the same entry if those requests are not treated by the same data source. For example, a client might make one request to change an entry and a second request to use the changed entry. If the second request is treated by a data source that has not been updated by the first request, an error occurs.

Client affinity can be configured in the following ways:

Client affinity takes precedence over the load balancing algorithm. Directory Proxy Server distributes a request from the specified connection to the specified data source, irrespective of the load balancing algorithm.

If client affinity is defined and enabled, the load balancing algorithm takes precedence in the following circumstances:

A data source cannot be used for a request in the following circumstances:

For information about how to configure client affinity, see Configuring Client Affinity in Sun Directory Server Enterprise Edition 7.0 Administration Guide.

The client affinity feature must be used to configure Directory Proxy Server as a simple, connection based router. For information, see Configuring Directory Proxy Server as a Connection Based Router in Sun Directory Server Enterprise Edition 7.0 Administration Guide.