Specify the webGrid feature to automatically start a container
that hosts clients for HTTP session replication.
You can set the following attributes on the xsWebGrid element
of the server.xml file:
Parameters
- objectGridType
A string value that is set to REMOTE, which specifies that session data is stored outside of the server
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 container servers.
- 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>. The host is the listener host on which the catalog server is running.
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 WebSphere® Application Server if the catalog.services.cluster property is configured.
- 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 the fragmentedSession parameter to true if the web application session has many attributes or attributes
with large sizes. Set fragmentedSession to false 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.
- credentialAuthentication
Indicates if credential authentication is enforced or supported.
- Never
No client certificate authentication is enforced.
- Required
- Credential authentication is always enforced. If the server does
not support credential authentication, the client cannot to connect
to the server.
- Supported
- (Default) Credential authentication is enforced only if both the
client and server support credential authentication.
- authenticationRetryCount
- Specifies the name of the class that implements the com.ibm.websphere.objectgrid.security.plugins.CredentialGenerator interface. This class is used to get credentials for clients. The
default value is 0.
- 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 is loaded
automatically if objectGridType=EMBEDDED and
the objectGridXML property is not specified.
- objectGridDeploymentXML
Specifies the location of the objectGrid deployment policy
XML file. The built-in XML file packaged in the eXtreme Scale library is loaded
automatically if objectGridType=EMBEDDED and
the objectGridDeploymentXML property is not specified.
- 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.
- ojectGridTxTimeout
- Specifies the amount of time in seconds that a transaction is
allowed for completion. If a transaction does not complete in this
amount of time, the transaction is marked for rollback and a TransactionTimeoutException exception results. Default value: 30 (in seconds)
- mapSetNumberOfPartitions
- Specifies the number of partitions for the mapSet element. Default
value: 47
- mapSetMinSyncReplicas
- Specifies the minimum number of synchronous replicas for each
partition in the mapSet. Shards are not placed until the domain can
support the minimum number of synchronous replicas. To support the
minSyncReplicas value, you need one more container server than the minSyncReplicas value. If the number of synchronous replicas
falls below the minSyncReplicas value, write
transactions are no longer allowed for that partition. Default value: 0
- mapSetMaxSyncReplicas
- Specifies the maximum number of synchronous replicas for each
partition in the mapSet. No other synchronous replicas are placed
for a partition after a domain reaches this number of synchronous
replicas for that specific partition. Adding container servers that
can support this ObjectGrid can result in an increased number of synchronous
replicas if your maxSyncReplicas value has not
already been met. Default value: 0
- mapSetMaxAsyncReplicas
- Specifies the maximum number of asynchronous replicas for each partition
in the mapSet. No other asynchronous replicas are placed for a partition
after a domain reaches this number of asynchronous replicas for that
specific partition. Adding container servers that can support this
ObjectGrid can result in an increased number of asynchronous replicas
if your maxAsyncReplicas value has not already
been met. Default value: 0
- mapSetDevelopmentMode
- With this attribute, you can influence where a shard is placed
in relation to its peer shards. When the developmentMode attribute
is set to false, no two shards from the same
partition are placed on the same computer. When the developmentMode
attribute is set to true, shards from the same
partition can be placed on the same machine. In either case, no two
shards from the same partition are ever placed in the same container
server. Default value: false