JMS Uniform Distribute Queue Unit Of Order, problem when one node goes down

Question

Hi ,
I have the following code which post a message (with Unit of Order set ) to a Uniform Distribute Queue in a cluster with two member servers (server1 and server2).
--UDQ is targeted to a subdeployment that is mapped to two JMS servers pointing to each member servers
--Connection Factory is using default targeting ( i tried mapping to Sub deployment also)
javax.naming.InitialContext serverContext = new javax.naming.InitialContext();
javax.jms.QueueConnectionFactory qConnFactory = (javax.jms.QueueConnectionFactory)serverContext.lookup(jmsQConnFactoryName);
javax.jms.QueueConnection qConn = (javax.jms.QueueConnection)qConnFactory.createConnection();
javax.jms.QueueSession qSession = qConn.createQueueSession(false, Session.AUTO_ACKNOWLEDGE);
javax.jms.Queue q = ( javax.jms.Queue)serverContext.lookup(jmsQName);
weblogic.jms.extensions.WLMessageProducer qSender = (weblogic.jms.extensions.WLMessageProducer) qSession.createProducer(q);
qSender.setUnitOfOrder("MyUnitOfOrder");
javax.jms.ObjectMessage message = qSession.createObjectMessage();
HashMap<String, Object> map = new HashMap<String, Object>();
map.put("something", "SomeObject");
message.setObject(map);
qSender.send(message);
} catch (Exception e) {           
Steps followed:
1. Post a message from "server1"
2. Message picked up by "server2"
3. Everything fine
4. Shutdown "server2"
5. Post a message from "server1"
6. ERROR: "hashed member of MyAppJMSModule!MyDistributedQ is MyAppJMSModule!MyJMSServer-2@MyDistributedQ which is not available"
WebLogic version : 10.3.5
Is there a way (other than configuring Path Service ) to make this code work "with unit of order" for a UDQ even if some member servers go down ?
Thanks very much for your time.

Answer 1

If you want to avoid use of the Path Service, then the alternative is to make the destination members highly available. This will help ensure that the host member for a particular UOO is up.
One approach to HA is to configure "service migration". For more information see the Automatic Service Migration white-paper at
http://www.oracle.com/technology/products/weblogic/pdf/weblogic-automatic-service-migration-whitepaper.pdf
In addition, I recommend referencing Best Practices for JMS Beginners and Advanced Users
http://docs.oracle.com/cd/E17904_01/web.1111/e13738/best_practice.htm#JMSAD455 to help with WL configuration in general.
Hope this helps,
Tom