Migrating EJB Applications to Support SFSB Failover

Application Server 7 does not support failover of Stateful Session Beans (SFSB). Application Server Enterprise Edition 8.2 supports failover of stateful session beans on the HTTP and RMI/IIOP path. This section describes the procedure to migrate EJB applications from Application Server 7 SE/PE/EE to Application Server 8.2 EE to support SFSB state failover.

Migrating EJB Applications From 7 SE/PE/EE to 8.2 EE

To achieve high availability of EJB applications that use stateful session beans to persist the data, you need to configure a persistent store for each cluster of application servers, where client session information can be maintained across potential failures of individual appserver instances. In addition, the availability-enabled flag must be turned on for each server instance in the cluster.

Application Server 8.2 EE supports the failover of stateful session beans. In order to enable this feature in your EJB applications that were deployed to Application Server 8.2 EE, follow the steps below:

To migrate Entity beans from previous releases of Sun’s Application Server, follow the procedure described in Entity Beans.

SFSB failover is supported when the SFSB is accessed from EJBs, servlets, or Java Server Pages in applications executing in the same application server process. The SFSB can be accessed through either a local or remote interface.

To take advantage of SFSB state failover support, you need not edit the code. However, you need to provide all the configuration parameters needed for checkpointing the SFSBs in the Sun-specific deployment descriptor (sun-ejb-jar.xml) or in the server configuration file.

For detailed information on SFSB failover, see Stateful Session Bean Failover in Sun Java System Application Server Enterprise Edition 8.2 High Availability Administration Guide.