To Enable Availability for the Web Container

  1. In the tree component, select the desired configuration.
  2. Click Availability Service.
  3. Click the Web Container Availability tab.
  4. Enable or disable availability.
  5. If availability is enabled, change other settings as follows:
    Persistence Type

    Specifies the session persistence mechanism for web applications that have availability enabled. Allowed values are as follows:

    memory

    Specifies no persistence.

    file

    Specifies the file system.

    replicated

    Specifies memory on other servers.

    ha

    Specifies HADB.

    Persistence Frequency

    Applicable only if the Persistence Type is ha or replicated.

    Specifies how often the session state is stored. Allowed values are as follows:

    web-method

    The session state is stored at the end of each web request prior to sending a response back to the client. This mode provides the best guarantee that the session state is fully updated in case of failure. This is the default.

    time-based

    The session state is stored in the background at the frequency set by the reapIntervalSeconds store property. This mode provides does not guarantee that session state is fully updated. However, it can provide a significant performance improvement because the state is not stored after each request.

    Persistence Scope

    Applicable only if the Persistence Type is ha or replicated. Specifies how much of the session object and how often session state is stored. Allowed values are as follows:

    session

    The entire session state is stored every time. This mode provides the best guarantee that your session data is correctly stored for any distributable web application. This is the default.

    modified-session

    The entire session state is stored if it has been modified. A session is considered to have been modified if HttpSession.setAttribute() or HttpSession.removeAttribute() was called. You must guarantee that setAttribute() is called every time an attribute is changed. This is not a Java EE specification requirement, but it is required for this mode to work properly.

    modified-attribute

    Only modified session attributes are stored. For this mode to work properly, you must follow a few guidelines:

    • Call setAttribute() every time the session state is modified.

    • Make sure there are no cross-references between attributes. The object graph under each distinct attribute key is serialized and stored separately. If there are any object cross references between the objects under each separate key, they are not serialized and deserialized correctly.

    • Distribute the session state across multiple attributes, or at least between a read-only attribute and a modifiable attribute.

    Single Sign-On State

    Check this box to enable persistence of the single sign-on state. To disable it, uncheck the box.

    HTTP Session Store

    Applicable only if the Persistence Type is ha. You can change the HTTP Session Store if you changed the JDBC resource used for connections to the HADB for session persistence. For details, see configure-ha-cluster(1).

    Persistence Store Health Check

    Applicable only if the Persistence Type is ha. Check this box to enable persistence store health check. To disable it, uncheck the box.

  6. If necessary, add or delete any additional properties.
  7. Click Save.
  8. Restart the server instance.