Java client support for high availability on IBM data servers

Client applications that connect to DB2® for Linux, UNIX, and Windows, DB2 for z/OS®, or IBM® Informix® can easily take advantage of the high availability features of those data servers.

Client applications can use the following high availability features:

• Automatic client reroute

  Automatic client reroute capability is available on all IBM data servers. Automatic client reroute uses information that is provided by the data servers to redirect client applications from a server that experiences an outage to an alternate server. Automatic client reroute enables applications to continue their work with minimal interruption. Redirection of work to an alternate server is called failover.

  For connections to DB2 for z/OS data servers, automatic client reroute is part of the workload balancing feature. In general, for DB2 for z/OS, automatic client reroute should not be enabled without workload balancing.

• Client affinities

  Client affinities is a failover solution that is controlled completely by the client. It is intended for situations in which you need to connect to a particular primary server. If an outage occurs during the connection to the primary server, you use client affinities to enforce a specific order for failover to alternate servers.

  Client affinities is not applicable to a DB2 for z/OS data sharing environment, because all members of a data sharing group can access data concurrently. Data sharing is the recommended solution for high availability for DB2 for z/OS.

• Workload balancing

  Workload balancing is available on all IBM data servers. Workload balancing ensures that work is distributed efficiently among servers in an IBM Informix high-availability cluster, DB2 for z/OS data sharing group, or DB2 for Linux, UNIX, and Windows DB2 pureScale® instance.

The following table provides links to server-side information about these features.