Data replication service

WebSphere Application Server provides a service that transfers data or events within clusters of like objects. The service is called WebSphere Internal Replication, or replication.

The replication service transfers both J2EE application data and any internal data used to maintain the application data among WebSphere Application Server runtime processes in a cluster of application servers. Currently, the Web container in WebSphere Application Server leverages data replication.

The replication service can replicate HttpSession data, including information on invalid data and actual cached data maintained by dynamic caching, among processes and retrieve the HttpSession if the process that currently maintains the HttpSession fails. Replication is a lower cost alternative to storing HTTPSession data in a relational database, and it is easier to administer.

For information about administering replication domains and replication entries, see Administer internal replication domains.

These topics provide additional information:

Replication domain
A replication domain is a collection of replication entries that are used together within a cell. See this topic for more information.

Replication entry
A replication entry is the runtime component that handles the transfer of data. See this topic for more information.