Session migration and replication

Question

Hi All,
I am having a hard time in configuring my application for HTTP session migration. Our weblogic server consists of two managed servers running in same cluster. Each server has an Ehcache that stores some information of user with key as session ID and value as info object. In case, if a server needs restart, we would want to take this updated info Object from cache residing on server being restarted to another managed server within the same cluster.
I browsed through many documentations online. Most of them explained about session replication but not migration. so I followed replication (I don't want a real time sync up of HTTP session. I want it to migrate if something goes wrong with one of the managed server).
However, I could not achieve this task after following the steps to configure this feature. I would appreciate a lot if someone can help me figuring out the issue here.
Here is what I did.
1) Weblogic.xml
     <session-descriptor>
<persistent-store-type>replicated_if_clustered</persistent-store-type>
</session-descriptor>
2) An implementation class of HttpSessionActivationListener, HttpSessionListener, HttSessionAttributeListener:
public void sessionDidActivate(HttpSessionEvent sessionEvent) {
// NEVER GETS CALLED
over here i would check if session has any attribute with name 'CACHE_ELEMENT'. If yes, then it is a migration case for current managed server
          Log.info(UserCacheMigrationListener.class, "inside sessionDidActivate");//
public void sessionWillPassivate(HttpSessionEvent sessionEvent) {
// NEVER GETS CALLED
Over here I would set attribute 'CACHE_ELEMENT' so that it is available for target managed server when it's sessionDidActivate is called
          Log.info(UserCacheMigrationListener.class, "inside sessionWillPassivate");
public void sessionCreated(HttpSessionEvent sessionEvent) {
THIS GETS CALLED! and I set the following attribute
sessionEvent.getHttpSession().setAttribute(UserCacheMigrationListener.class.getName(), this);
public void sessionDestroyed(HttpSessionEvent arg0) {
THIS GETS CALLED!
public void valueBound(HttpSessionBindingEvent arg0) {
THIS GETS CALLED! WHICH MEANS THAT I WAS ABLE TO setAttribute this class's instance in sessionCreatedMethod
In the above code, the setAttribute method used inside the sessionCreated(..) method successfully sets the attribute to this session. This is apparent because valueBound(..) method is called when session is created. But why does it not call the sessionWillActivate method???
3.) An entry in web.xml for this listener.
     <listener>
          <listener-class>com.xyz.UserCacheMigrationListener</listener-class>
     </listener>
4) from weblogic config.xml. I am copying all meaning stuffs from config.xml to describe as much as I can.
<server>
<name>AdminServer</name>
<ssl>
<enabled>false</enabled>
</ssl>
<listen-address>localhost</listen-address>
<network-access-point>
<name>AdminChannel</name>
<protocol>t3</protocol>
<listen-address>localhost</listen-address>
<http-enabled-for-this-protocol>true</http-enabled-for-this-protocol>
<tunneling-enabled>false</tunneling-enabled>
<outbound-enabled>false</outbound-enabled>
<enabled>true</enabled>
<two-way-ssl-enabled>false</two-way-ssl-enabled>
<client-certificate-enforced>false</client-certificate-enforced>
</network-access-point>
<data-source>
<rmi-jdbc-security xsi:nil="true"></rmi-jdbc-security>
</data-source>
</server>
<server>
<name>Node1</name>
<ssl>
<enabled>false</enabled>
</ssl>
<machine>DevMachine</machine>
<listen-port>7002</listen-port>
<cluster>DevCluster</cluster>
<replication-group>devGroup1</replication-group>
<preferred-secondary-group>devGroup2</preferred-secondary-group>
<web-server>
<keep-alive-secs>500</keep-alive-secs>
<post-timeout-secs>120</post-timeout-secs>
</web-server>
<listen-address>localhost</listen-address>
<jta-migratable-target>
<user-preferred-server>Node1</user-preferred-server>
<cluster>DevCluster</cluster>
</jta-migratable-target>
<data-source>
<rmi-jdbc-security xsi:nil="true"></rmi-jdbc-security>
</data-source>
</server>
<server>
<name>Node2</name>
<ssl>
<enabled>false</enabled>
</ssl>
<machine>DevMachine</machine>
<listen-port>7003</listen-port>
<cluster>DevCluster</cluster>
<replication-group>devGroup2</replication-group>
<preferred-secondary-group>devGroup1</preferred-secondary-group>
<listen-address>localhost</listen-address>
<network-access-point>
<name>Node2Channel</name>
<protocol>t3</protocol>
<listen-address>localhost</listen-address>
<http-enabled-for-this-protocol>true</http-enabled-for-this-protocol>
<tunneling-enabled>true</tunneling-enabled>
<outbound-enabled>false</outbound-enabled>
<enabled>true</enabled>
<two-way-ssl-enabled>false</two-way-ssl-enabled>
<client-certificate-enforced>false</client-certificate-enforced>
</network-access-point>
<jta-migratable-target>
<user-preferred-server>Node2</user-preferred-server>
<cluster>DevCluster</cluster>
</jta-migratable-target>
<data-source>
<rmi-jdbc-security xsi:nil="true"></rmi-jdbc-security>
</data-source>
</server>
<cluster>
<name>DevCluster</name>
<cluster-messaging-mode>unicast</cluster-messaging-mode>
</cluster>
<machine>
<name>DevMachine</name>
<node-manager>
<nm-type>Plain</nm-type>
</node-manager>
</machine>
<migratable-target>
<name>Node1 (migratable)</name>
<notes>This is a system generated default migratable target for a server. Do not delete manually.</notes>
<user-preferred-server>Node1</user-preferred-server>
<cluster>DevCluster</cluster>
</migratable-target>
<migratable-target>
<name>Node2 (migratable)</name>
<notes>This is a system generated default migratable target for a server. Do not delete manually.</notes>
<user-preferred-server>Node2</user-preferred-server>
<cluster>DevCluster</cluster>
</migratable-target>
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Answer 1

Hi,
So you want to migrate your server to server.
Here are the following links which help you.
http://docs.oracle.com/cd/E15051_01/wls/docs103/cluster/migration.html
http://www.oracle.com/technetwork/middleware/weblogic/messaging/wlasm-1853193.pdf
let me know the status if you need any further help on this issue.
Regards,
Kal