Sun Java System Application Server Enterprise Edition 8.1 2005Q2 Quick Start Guide

Verifying HTTP Session Failover

The steps for testing session data failover are similar for testing load balancing as described in the topic Verifying Load Balancing. This time Session Data is preserved after failure. Failover is transparent to the user because the sample application is configured for automatic retry after failure.

ProcedureTo Verify HTTP Session Failover

  1. To display the first page of the clusterjsp application, type this URL in your browser:


    Replace the localhost variable with the name of the system that the Web Server is running on.

    Replace the web_server_port variable with the value of the port attribute of the LS element in web_server_install_dir/https-hostname/config/server.xml. For this example, port 38000 is used.

    A page similar to what you saw in To Verify the Application Deployment appears.

  2. Examine the Session and Host information displayed. For example:

    • Executed From Server: localhost

    • Server Port Number: 38000

    • Executed Server IP Address:

    • Session ID: 41880f618e4593e14fb5d0ac434b1

    • Session Created: Wed Feb 23 15:23:18 PST 2005

  3. View the server access log files to determine which application server instance is serving the application. The log files are located here:

    • Solaris Java Enterprise System installation:



    • Linux Java Enterprise System installation:



    • Windows Java Enterprise System installation:



    • Standalone Application Server installations:



  4. Stop the Application Server instance that is serving the page.

    1. In the Admin Console, in the left pane, expand Clusters.

    2. Click FirstCluster.

    3. In the right pane, click the Instances tab.

    4. Click the checkbox next to the server instance that served the request and click the Stop button.

  5. Reload the clusterjsp sample application page.

    The session ID and session attribute data is retained.

  6. Check the access log of the other Application Server instance, and notice that it is now servicing the request.

    The state failover features work because the HTTP session is stored persistently in the HADB. In addition to the HTTP session state, the Application Server also can store the state of EJBTM enterprise beans in the HADB.