Websphere 6.1 and JMX Weirdness

[Aoife Kavanagh]

Hi,

We're upgrading from Websphere ND 6.0 to 6.1 and everything has gone fine except around the area of JMX.
Short story:
1. We deploy a WAR file containing all the jars that the war requires to run.
2. Set class loading to "Classes loaded with application class loader first" and "Single class loader for application"
3. On startup our application creates its own MBeanServer. We use mx4j for this shipping mx4j.jar, mx4j-tools.jar and mx4j-jmx.jar in WEB-INF\lib directory of our deployed application.
4. When our application makes call

MBeanServerFactory.createMBeanServer()

we get the exception:

javax.management.JMRuntimeException: Specified MBeanServerBuilder must be a subclass of MBeanServerBuilder: class com.ibm.ws.management.PlatformMBeanServerBuilder
at javax.management.MBeanServerFactory.createMBeanServerBuilder(MBeanServerFactory.java:236)
at javax.management.MBeanServerFactory.createMBeanServerImpl(MBeanServerFactory.java:195)
at javax.management.MBeanServerFactory.createMBeanServer(MBeanServerFactory.java:44)
at javax.management.MBeanServerFactory.createMBeanServer(MBeanServerFactory.java:39)
at com.fineos.ta.jmx.TaJmxResource.getMBeanServer(TaJmxResource.java:147)

I know that classloading in Websphere 6.1 is different to previous releases but these changes are not supposed to affect deployed applications. I'm just wondering if anybody has any idea what might be the problem here as this is a major issue for us and we've had PMR with IBM open for a few weeks now with no joy so far.

Regards,
Aoife

[Erik Vaneylen]

Hi, I'm having the exact same problem..
Did you by any chance solve it?

It works if I'm using a single classloader for both Websphere and the App, and then use the MBeanServer of websphere by getting a reference like this:

server = (MBeanServer) MBeanServerFactory.findMBeanServer(null).get(0);

However this is not what I want. I would like to start my own instance of an MBeanServer.

regards,

Erik

[Aoife Kavanagh]

Hi Eric,

No, we still have not heard anything back from IBM regarding this. If/when we get a solution from IBM I will post it to this group.

Regards,
Aoife

[Erik Vaneylen]

Hi,

I use the newMBeanServer methode instead of createMBeanServer.
But the same problem occured in 6.1.0.5. However in 6.1.0.7 this has been fixed.

greetz

[Aoife Kavanagh]

Hi,

We came to the conclusion that the problem, if it can be called that, is due to changes in Java 1.5. We noticed, as a result of application diagnostics that when we ran over our application in 2tier or over other middlewares using the Sun 1.5 JDK that it wasn't an mx4j class being instantiated for the mbeanserver, but a Sun one. Prior to 1.5 it was an MX4J class being used. We got everything working fine by just removing mx4j.jar from classpath though we are still using classes from mx4j-tools.jar

Aoife

[Tepih Taskuhwilly]

just do this if you have mx4j in classpath...

System.setProperty("javax.management.builder.initial","mx4j.server.MX4JMBeanServerBuilder");