WebSphere Application Server includes a high availability manager component. The services that the high availability manager provides are only available to WebSphere Application Server components.
A high availability manager provides several features that allow other WebSphere Application Server components to make themselves highly available. A high availability manager provides:
* A framework that allows singleton services to make themselves highly available. Examples of singleton services that use this framework include the transaction managers for cluster members, and the default IBM® messaging provider, also known as the service integration bus.
* A mechanism that allows servers to easily exchange state data. This mechanism is commonly referred to as the bulletin board.
* A specialized framework for high speed and reliable messaging between processes. This framework is used by the data replication service when WebSphere Application Server is configured for memory-to-memory replication.
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