MQSeries.net :: View topic - MQ JMS API, XA recovery issue, Weblogic as TM

abhay09 · Posted: Thu Jul 14, 2016 9:33 pm Post subject:

Hi All,

We are using MQ JMS API to connect to MQ and all message flows are under XA transaction using Weblogic Transaction manager

While testing XA recovery, we faced one issue and need help.

Scenario:

1.) 2 QM ,
2.) Read from one QM (Queue1 ) and put into other QM (Queue2) using MQ JMS API.
3.) Weblogic as Transaction Manager
4.) Application hosted on WL

To test recovery, we forcefully killed the server on "prepare()" method of XA resource by using System.exit(1).

public int prepare(Xid xid) throws XAException {
System.exit(1);
return resource.prepare(xid);
}

Now, my application:
- Started a transaction
- Enlisted QM 1 (Queue1) XA resource
- Get message from MQ QM 1 (Queue1)
- Enlisted QM 2 (Queue2) XA resource
- Called txn.commit() method
- As this is Xa transaction , so it will 2 phase commit
- Prepare method will be called
- And System crashes

- After Crash, observations

- Message rollbacked to MQ QM 1 (Queue1)
- But there is increase in count of QM 2 (Queue2), but cant browse any message

- Updated code to remove System.exit(1);
- Build code

- On restart of Weblogic

- No transaction is pending under WL as nothing mentioned in logs and WL console

- WL started a new txn and read message from QM 1 (Queue1) and delivered to QM 2( Queue2)

- Now, count of QM2 (Queue 2) increased to 2.

- Can browse only 1 out of 2

So, question is why QM2 (Queue 2) count increased when server crashed
and for WL transaction rollbacked , so no pending txn for recovery.

Please let me know how to handle this case.

Why QM 2( Queue2) count increases when transaction is roll backed.

Please let me know for any more information.