Persistence schema for load-balancing and failover support

The Bank Transformation Toolkit provides base infrastructure persistence functionality for high availability solutions (24x7) using a load-balancing mechanism among a set of server clones, each running a toolkit-based environment. The functions include the following:

The WebSphere family of products provide load-balancing, failover, and session affinity. An application running in this kind of environment must be properly designed to use these features. For example, requests can be routed to any of the available nodes or clones that contain the server side logic of the application. This means that the solution must not make any assumptions regarding the availability of previous state information in memory, and instead must store the required state so that it can be shared across many requests in a data store. Thus, when a server clone processes a request, it saves the state information into a database to allow other server clones to restore the information to process another request. In the toolkit environment, you configure WebSphere to use multiple rows of server clones to get better performance. The objective is for the use of multiple server clones to be transparent to the client while providing superior performance and availability. The actual behavior depends on the proper configuration of WebSphere, such as cache settings and the policy for session affinity, and the configuration of the toolkit itself.

Refer to the WebSphere documentation for information on properly configuring the WebSphere platform for multiple server environment support. For the toolkit, see Configuration for session persistence and session affinity.