HP Integrity NonStop H-Series - Manual (Page 60)

store as illustrated in Figure 2 (page 14) . In NSASJ, the embedded caches are in local mode and
do not share any data. Instead, when the clustered session information is put into the cache, it is
evicted to the remote backup store in the Infinispan Cache servers. Session data requests are
obtained by querying the remote backup store in Infinispan Cache servers. Thus, when requests
span across instances of NSASJ, the most recent data is obtained from the remote store. Also, the
remote store Infinispan Cache servers are configured to form a cluster, and are in distributed mode
to avoid any single point of failure.
Session replication configuration for NSASJ
For an application to have session replication on failover, the application must be distributable.
The following section describes the way to achieve session replication:
Indicate that the application is distributable. If the application is marked as distributable, the session
details are stored in the cache. To achieve this, add the element inside the
tag of the application's web.xml file. The following example depicts the only
configuration change in the application:
Example 2 Sample snippet
http://java.sun.com/xml/ns/j2ee
" xmlns:xsi= http://www.w3.org/2001/XMLSchema-instance
xsi:schemaLocation=" http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd ">
The default configuration given with NSASJ takes care of session replication.
Infinispan subsystem in domain.xml
The following snippet is a sample depicting the default configuration for session replication:
module="org.jboss.as.clustering.web.infinispan">
passivation="false" fetch-state="false" purge="false">
Table 15 Components of domain.xml
Description Attribute Element
For session replication, NSASJ looks for a cache container
by name web. name cache container
The alias has to be standard-session-cache as NSASJ
looks for cache with the alias for session replication. alias
Can be any local cache defined in the subsystem. default-cache
The module used for session replication and has to be
org.jboss.as.clustering.web.infinispan
.
module
The embedded cache in NSASJ is a local cache and acts
as a cache loader. name local-cache
This value has to be set to true. batching
This cache must be started on server startup. start
The named cache in Infinispan Cache server that acts as
the backup store cache and stores the session information. cache remote-store
The timeout value to wait for socket connections to the
Infinispan Cache server. socket-timeout
60 Configuring NSASJ