Re: [xmlblaster] Client connection not being restored properly?

[Marcel Ruff]

Hi David,

if the server side session times out the expected behavior is
that the client goes to dead (what you client seem to do).
That your client recovers from DEAD is not intended
and is considered a bug, see
http://www.xmlblaster.org/xmlBlaster/doc/requirements/client.failsafe.html#failsave
The transition (9) and (8) should not happen.


Thanks for reporting
best regards
Marcel


David Kerry wrote:

On Mon, Mar 10, 2008 at 11:10:54AM +0100, Marcel Ruff wrote:

Hi David,

fail safe mode should also set a positive session id,
like this the client queue is found again on restart and
you don't need another queue to store the entries.

Something like

java -Dcom.sun.management.jmxremote javaclients.HelloWorldSubscribe -session.name subscriber/1 -dispatch/callback/retries -1 -connect/qos/persistent true -persistentSubscribe true

The persistent settings are only needed to recover from server restart and to not

loose a message if a publisher reconnects and publishes earlier,
before our subscriber reconnects and re-subscribes.

best regards,
Marcel

Hi Marcel,

Something's still fishy here.  Although I'm not setting a persistent
queue (I'm not concerned about queued incoming messages while disconnected

right now), I am setting all the other parameters for a failsafe connection (callback retries -1, positive session id).

I've setup my client to be notified of connection state via the
I_ConnectionStateListener interface.

When I attempt to publish a message after the session times out, I get
a callback when the session times out (reachedDead), which is correct.

However, what's not happening reliably is the reachedPolling state.
Most of the time my test client goes reachedDead -> reachedPolling -> 
reachedAlive.
In some cases it just goes reachedDead and no further.

I did note this exception that popped out on the client side in a case

where the client didn't get to a polling state. I don't know if it's relevant or not though. I didn't see any other log output or exceptions around

the time this occurred.  The server side simply indicates the session timed out.

2008-04-01 13:45:36,602 INFO  [STDOUT] java.lang.Exception: Stack trace
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
java.lang.Thread.dumpStack(Thread.java:1158)
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
org.xmlBlaster.client.ClientErrorHandler.handleError(ClientErrorHandler.java:79)
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
org.xmlBlaster.util.dispatch.DispatchManager.givingUpDelivery(DispatchManager.java:379)
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
org.xmlBlaster.util.dispatch.DispatchManager.shutdownFomAnyState(DispatchManager.java:371)
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
org.xmlBlaster.util.dispatch.DispatchConnectionsHandler.updateState(DispatchConnectionsHandler.java:368)
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
org.xmlBlaster.util.dispatch.DispatchConnectionsHandler.toDead(DispatchConnectionsHandler.java:336)
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
org.xmlBlaster.util.dispatch.DispatchConnection.handleTransition(DispatchConnection.java:498)
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
org.xmlBlaster.util.dispatch.DispatchConnection.send(DispatchConnection.java:241)
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
org.xmlBlaster.util.dispatch.DispatchConnectionsHandler.send(DispatchConnectionsHandler.java:455)
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
org.xmlBlaster.util.dispatch.DispatchWorker.run(DispatchWorker.java:70)
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
org.xmlBlaster.util.dispatch.DispatchManager.putPre(DispatchManager.java:668)
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
org.xmlBlaster.util.dispatch.DispatchManager.putPre(DispatchManager.java:642)
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
org.xmlBlaster.util.queue.ram.RamQueuePlugin.put(RamQueuePlugin.java:723)
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
org.xmlBlaster.client.XmlBlasterAccess.queueMessage(XmlBlasterAccess.java:901)
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
org.xmlBlaster.client.XmlBlasterAccess.publish(XmlBlasterAccess.java:1061)
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
com.navahonetworks.app.jboss.xmlblaster.NNXmlBlasterClientImpl.publish(NNXmlBlasterClientImpl.java:165)
2008-04-01 13:45:36,603 INFO  [STDOUT]  at 
com.navahonetworks.app.jboss.xmlblaster.NNXmlBlasterClientImpl.publish(NNXmlBlasterClientImpl.java:138)
2008-04-01 13:45:36,604 INFO  [STDOUT]  at 
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
2008-04-01 13:45:36,604 INFO  [STDOUT]  at 
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
2008-04-01 13:45:36,604 INFO  [STDOUT]  at 
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
2008-04-01 13:45:36,604 INFO  [STDOUT]  at 
java.lang.reflect.Method.invoke(Method.java:585)
2008-04-01 13:45:36,604 INFO  [STDOUT]  at 
com.navahonetworks.ejb.session.XmlblasterLogicBean.publish(XmlblasterLogicBean.java:287)
2008-04-01 13:45:36,604 INFO  [STDOUT]  at 
com.navahonetworks.ejb.session.XmlblasterLogicBean.publish(XmlblasterLogicBean.java:372)
2008-04-01 13:45:36,604 INFO  [STDOUT]  at 
com.navahonetworks.ejb.session.XmlblasterLogicBean$TxSyncThread.run(XmlblasterLogicBean.java:809)
2008-04-01 13:45:36,605 ERROR [STDERR] 1-Apr-2008 1:45:36 PM 
org.xmlBlaster.util.dispatch.DispatchManager switchToASyncMode
INFO: connection:client/app_prod/12: Switched to asynchronous message delivery

--
Marcel Ruff
http://www.xmlBlaster.org
http://watchee.net
Phone: +49 7551 309371