Different behaviour in JMS Cluster automatic failover

Question

Hi,
          I am problem in JMS clustering, now let me explain the scenario.
          I have 2 managed servers participating in the weblogic cluster, now since JMS is a singleton service what i did is i have created 2 JMS servers and targeted them to Managedservers 1 and 2 respectively.I have also created a Distributed Destination and deploy they with the deployment "wizard" ("autodeploy") to all the member of the cluster.
          Now in my case I created two different type of client
          Asynchronous and synchronous .
          The first one register himself as MessageListener and also as ExceptionListener. When I bring down the managed server in which the client is connect the call back method onException is called.
          The second client instead register himself as ExceptionListener but not as MessageListener. It call in different thread the receive method on the destination.
          In this case if i I bring down the managed server in which the client is connect the call back method onException is NOT called, instead i receive the JMSException on all the call "receive".
          I expected that the behaviour was the same of the firts client.
          Thanks in advance.
          dani

Answer 1

Its not clear from your description what you're trying to do, as typical apps use a single module, including those that use distributed destinations, and typical apps do not use the convention of specifying a module name in their JNDI name. (The "!" syntax makes me suspect that you're not using JNDI to lookup destinations, rather you're using the rarely recommended JMS session "createQueue()" call.).
Never-the-less, I suspect the problem is simply that your using a distributed queue and haven't realized that queue browsers and consumers pin themselves to a single queue member. To ensure full coverage of a distributed queue, the best practice is to use a WebLogic MDB: WebLogic MDBs automatically ensure that each queue member has consumers.
By the way, if you are using a distributed queues, then the best practice config is as follows for each homogeneous set of JMS servers:
-- Configure a custom WL store per server, target to the server's default migratable target.
-- Configure a JMS server per server, target to the server's default migratable target, set the store for the JMS server to be the same as the custom store.
-- Configure a single JMS module, target to the cluster.
-- Configure a single subdeployment for the module that references each JMS server (and nothing else).
-- Configure one or more distributed queues for the module. Never use default targeting -- instead use advanced subdeployment targeting to target each distributed queue to the single subdeployment you defined earlier.
-- Configure one or more custom connection factories in the module, use default targeting.
I recommend that you read through the JMS admin and programmer's guides in the edocs if you haven't done so already. You might find that the JMS chapter of the new book "Professional Oracle WebLogic" is helpful.
Tom
Edited by: TomB on Nov 4, 2009 10:12 AM