Administration guide > Configure the deployment environment > Configuring cache integration > Configuring HTTP session managers



Servlet context initialization parameters

The following list of servlet context initialization parameters can be specified in the splicer.properties file as required in the chosen splicing method.


Parameters

objectGridType

A string value of either "REMOTE" or "EMBEDDED". The default is REMOTE.

If it is set to "REMOTE", the session data will be stored outside of the server on which the web application is running.

If it is set to "EMBEDDED", an embedded eXtreme Scale container will start in the application server process on which the web application is running.

objectGridName

A string value that defines the name of the ObjectGrid instance used for a particular web application. The default name is session.

This property must reflect the objectGridName in both the objectgrid XML and deployment XML files used to start the eXtreme Scale containers.

catalogHostPort

The catalog server can be contacted to obtain a client side ObjectGrid instance. The value must be of the form host:port<,host:port>, where the host is the listener host on which the catalog server is running, and the port is the listener port for that catalog server process. This list can be arbitrarily long and is used for bootstrapping only. The first viable address is used. It is optional inside WAS if the catalog.services.cluster property is configured.

replicationInterval

An integer value (in seconds) that defines the time between writing of updated sessions to ObjectGrid. The default is 2. Possible values are from 0 to 60. 0 means that updated sessions are written to the ObjectGrid at the end of servlet service method call for each request. A higher replicationInterval value improves performance because fewer updates are written to the data grid. However, a higher value makes the configuration less fault tolerant.

This setting applies only when objectGridType is set to "REMOTE".

sessionTableSize

An integer value that defines the number of session references kept in memory. The default is 2000.

This setting pertains only to a REMOTE topology because the EMBEDDED topology already has the session data in the same tier as the web container.

Sessions are evicted from the in-memory table based on Least Recently Used logic. When a session is evicted from the in-memory table, it is invalidated from the web container. However, the data is not removed from the grid, so subsequent requests for that session can still retrieve the data. This value should be set higher than the web container maximum thread pool value, which reduces contention on the session cache.

fragmentedSession

A string value of either "true" or "false." The default value is "true." Use this setting to control whether the product stores session data as a whole entry, or stores each attribute separately.

Set fragmentedSession to "true" if the web application session has many attributes or attributes with large sizes. Set fragmentedSession to "false" only if a session has few attributes, because all the attributes are stored in the same key in the data grid.

In the previous, filter-based implementation, this property was referred to as persistenceMechanism, with the possible values of ObjectGridStore (fragmented) and ObjectGridAtomicSessionStore (not fragmented).

securityEnabled

A string value of either "true" or "false." The default value is "false." This setting enables eXtreme Scale client security. It must match the securityEnabled setting in the eXtreme Scale server properties file. If the settings do not match, an exception occurs.

credentialGeneratorClass

The name of the class that implements the com.ibm.websphere.objectgrid.security.plugins.CredentialGenerator interface. This class is used to obtain credentials for clients.

credentialGeneratorProps

The properties for the CredentialGenerator implementation class. The properties are set to the object with the setProperties(String) method. The credentialGeneratorProps value is used only if the value of the credentialGeneratorClass property is not null.

objectGridXML

The file location of the objectgrid.xml file. The built-in XML file packaged in the eXtreme Scale library will be loaded automatically if objectGridType=EMBEDDED and the objectGridXML property is not specified.

objectGridDeploymentXML

Specifies he location of the objectGrid deployment policy XML file. The built-in XML file packaged in the eXtreme Scale library will be loaded automatically if objectGridType=EMBEDDED and the objectGridDeploymentXML property is not specified.

traceSpec

Specifies the IBM WebSphere trace specification as a string value. Use this setting for application servers other than WAS.

traceFile

Specifies the trace file location as a string value. Use this setting for application servers other than WAS.

[Fix 1 and later] cookieName

Overrides the servlet specification that is designated as the cookie or encoded URL name of JSESSIONID. If the cookieName value is changed from JSESSIONID, configure the application servers to use this value as well.

[Fix 1 and later] cookieDomain

Specifies if you require sessions to be accessible across hosts. Set the value to the name of the common domain between the hosts.

[Fix 1 and later] reuseSessionID

Set to true if the underlying web container reuses session IDs across requests to different hosts. The default value is false. The value of this property must be the same as the value in the web container.

[Fix 1 and later] shareSessionsAcrossWebApps

Specifies if sessions are shared across web applications, specified as a string value of either true or false. The default is false. The servlet specification states that HTTP Sessions cannot be shared across web applications. An extension to the servlet specification is provided to allow this sharing.


Parent topic:

Configure HTTP session managers


Related tasks

Configure the HTTP session manager with WAS

[Fix 1 and later] Configure HTTP session manager with WebSphere Portal

Configure the HTTP session manager for various application servers

Related reference

XML files for HTTP session manager configuration