How to turn off session replication in JBoss 4.0.4?

[somejunk]

Hi,

We are having two JBoss 4.0.4 on the same machine in a cluster in active-active way.With active active cluster, we are running into serializable exceptions because of session replication and are experiencing unacceptable latency. So we have decided to use cluster just for fail over and not for session replication.

I know that our code has objects that are not implementing serializable interface but at this stage we cannot afford to change it. we also feel that we do not have to change it if we are not going for session relication.

After reading some of the posts here and refering couple of other documents, I found out that change of cache mode attribute to local should turn off sessio replication. Also we are using modjk, so I commented out the following

instant
2000

and

jboss.cache:service=TomcatClusteringCache

jboss:service=TransactionManager

Even after making these changes, I still see serializable exceptions.
I am not sure if session replication is happening or not. We do not want session replication, please advice me on the changes that I need to make to turn off session replication...Thanks

[somejunk]

Since we are using modjk, I also commented out the following snapshot mode attributes:

name="SnapshotMode">instant
name="SnapshotInterval">2000

[brian.stansberry]

Just remove the

<distributable/>

element from your web.xml; that's all you need to do. Leave the other stuff as is.

BTW, when you post XML, use the 'code' button to put in tags before and after. That's the trick to making it appear correctly. :-)

[somejunk]

Thanks for your reply...

If I understand it correctly, I do not have to change anything in JBoss to turn off session replication.
I just have to remove distributable tag from web.xml in the ear file. Is that right?

[brian.stansberry]

Yep; that's it.

If you're never going to deploy any distributable webapps and want to remove the service that makes session replication possible, you can remove the tc5-cluster.sar and comment out the

<depends>jboss.cache:service=TomcatClusteringCache</depends>

tag in jbossweb-tomcat55.sar/META-INF/jboss-service.xml.

See http://wiki.jboss.org/wiki/Wiki.jsp?page=JBossASTuningSliming for more on removing unwanted services; clustering stuff covered at the bottom. But again, if web.xml doesn't have the distributable tag, that webapp won't use session replication.

[somejunk]

Thanks it works fine now...

I noticed that fail over is seamless to end user. How is this possible without session replication?