Help required on In memory session replication

[Shiv Kumar MN <sh...@majoris.com>]

Hello Fillip,

I am trying to setup Tomcat clustering to achieve:
    1. Load balancing
    2. Fail over

I am referring to your article on this "www.theserverside.com"
and Pascal Forget's article on "www.ubeans.com". I having some
problem in getting it work. Could you please help me on this?

What I have done:

1. I followed what Pascal Forget article says, also I have verified
    after these steps that Tomcat/Apache is really doing load balancing.
    This part of it is working fine.
2. Now I followed the steps indicated in your article to integrate your
    method and Pascal Forget's method so that I get load balancing
    as well as fail over without loosing session.

    After following the steps and restarting Tomcat-1, Tomcat-2 followed
    by Apache, I see some error logs in both Tomcat's "logs" directory, log
    file "localhost_log.2002-06-15.txt". The error is:

    java.lang.NullPointerException
        at
org.apache.catalina.session.InMemoryReplicationManager.createSession(InMemoryReplicationManager.java:212)

    I have attached this complete for your reference. Please let me know
    where I am going wrong.

Setup Environment:

Tomcat-1:
Linux v6.2, JDK 1.4 (J2SE)

Tomcat-2:
Solaris v2.7 SPARC Ent 450 server, JDK 1.4 (J2SE)

Apache:
Linux v6.2, mod_jk, Apache v1.3.24

Thank you for your help and time,

Best Regards,
 - Shiv.