I am not certain about this but I think the version mismatch was discovered because the ackType in the exception was = 6, and someone (not me because at that time I was not involved with the project) noticed that v5.5.1 did not support ackType = 6, i.e. the max ackType for v5.5.1 is 5.
I don't know if the client was using failover transport. I'm not sure if this was ever investigated but I can try to find out. Thanks for your thoughts. Michael Tarullo Contractor (Engility Corp) Software Engineer FAA WJH Technical Center (609)485-5294 -----Original Message----- From: artnaseef [mailto:a...@amlinv.com] Sent: Thursday, September 01, 2016 12:05 PM To: users@activemq.apache.org Subject: Re: Need Help With A JMS Exception A couple of thoughts on this front. First, how was the conclusion of different client versions made? I'm curious because I can't think of any way that should be an issue. Second, is the consumer using the failover transport? This JMS Exception can happen normally without indicating a problem, especially with the failover transport, as the consumer may then send an acknowledgement to the broker after it has already received another acknowledgement for the same message. Or, with Topics, the rebuilt subscription may not have the message - I'm not sure how the failover transport handles non-durable Topic subscriptions. My suspicion is that the new subscription, after failover, will start fresh, with none of the old messages. So, if the consumer then proceeds to send an acknowledgement for the message, the broker won't be able to match the message. On Thu, Sep 1, 2016 at 11:13 AM, Michael.CTR.Tarullo [via ActiveMQ] < ml-node+s2283324n4716062...@n4.nabble.com> wrote: > Thanks Matt. And yes I was aware of the behavior of CLIENT_ACK, > although when I started this research I was not. Before this I was > under the impression that it was a single message ack. > > Michael Tarullo > Contractor (Engility Corp) > Software Engineer > FAA WJH Technical Center > (609)485-5294 > > > -----Original Message----- > From: Matt Pavlovich [mailto:[hidden email] > <http:///user/SendEmail.jtp?type=node&node=4716062&i=0>] > Sent: Thursday, September 01, 2016 10:58 AM > To: [hidden email] > <http:///user/SendEmail.jtp?type=node&node=4716062&i=1> > Subject: Re: Need Help With A JMS Exception > > +1 Agree that debugging it is the only surefire way to understand what > is going on. > > On a side note-- CLIENT_ACKNOWLEDGE is kludgy of sorts. Be sure to > understand that it acknowledges the current message and _all_ previous > messages. It isn't an individual message acknowledgement as most > people are hoping. To get that, you need to use ActiveMQ's extension > ActiveMQSession.INDIVIDUAL_ACKNOWLEDGE or go full blown TRANSACTED. > > All JMS providers have this "extended" ack mode and there is a JMS > feat request to make INDIVIDUAL_ACKNOWLEDGE a standardized thing: > > Vote here: https://java.net/jira/browse/JMS_SPEC-95 > > On 9/1/16 7:47 AM, Tim Bain wrote: > > > Since you have the 5.5.1 source code, I recommend you attach a > > debugger > to > > the broker process and set a breakpoint on the > > TopicSubscription.acknowledge() method; the stack will tell you how > > you > got > > there. Setting breakpoints on the broker can lead to instability > > and > may > > force you to restart it (plus you have to restart it to enable the > > debug port and again to disable it, and it's a security > > vulnerability while > it's > > open), so do this in a dev/test environment, not a production one. > > > > You should not expect that there would be a call chain between the > > two methods you referenced. One is executed on the client and one > > is > executed > > on the broker, so between the two there is the creation, > > transmission, > and > > handling of the acknowledgement message. > > > > Tim > > > > On Aug 31, 2016 4:15 PM, <[hidden email] > <http:///user/SendEmail.jtp?type=node&node=4716062&i=2>> wrote: > > > >> We had a rather unique situation some time ago where our message > >> broker log was recording the JMSException for an Invalid acknowledgement. > >> > >> We traced it to the fact that the consumer of the message was using > >> a > more > >> recent version of ActiveMQ than our message broker was running (i.e. > >> message broker was v5.5.1 and the consumer was >v5.5.1). > >> > >> We would like to recreate this error in one of our test > >> environments so that we can learn more about it. > >> > >> It appears that the exception was related to a consumer > >> acknowledging a message. We determined this from observing that > >> the specific exception that was thrown appears to originate in only > >> one place, that is the > >> acknowledge() function of the TopicSubscription class. > >> > >> I have configured an environment with a v5.5.1 message broker and a > >> consumer and producer compiled with v5.11.0 of ActiveMQ. The > >> producer sends messages to a topic and the consumer receives these > >> messages and > then > >> acknowledges those messages. The session was configured for client > >> acknowledgement. Under these conditions I could not reproduce the > >> exception described above. > >> > >> I tried looking through the source code for the acknowledge() > >> function > of > >> the ActiveMQMessage class to see if I could determine how my > >> consumer > call > >> to acknowkedge() landed on the TopicSubscription acknowledge(), but > have > >> been unable to make a connection between the acknowledge() function > >> in ActiveMQMessage and TopicSubscription even after following the > >> calls starting with the call to ActiveMQMessage acknowledge(). > >> > >> Can you offer any explanation as to why I am unable to trace the > functions > >> calls to TopicSubscription acknowledge? And more importantly, can > >> you offer any advice on how I might recreate the exception > >> condition > described > >> here? > >> > >> Thanks, > >> Mike > >> > >> Michael Tarullo > >> Contractor (Engility Corp) > >> Software Engineer > >> FAA WJH Technical Center > >> (609)485-5294 > >> > >> > > > > ------------------------------ > If you reply to this email, your message will be added to the > discussion > below: > http://activemq.2283324.n4.nabble.com/Need-Help-With-A-JMS-Exception- > tp4716045p4716062.html > To start a new topic under ActiveMQ - User, email > ml-node+s2283324n234180...@n4.nabble.com > To unsubscribe from ActiveMQ - User, click here > <http://activemq.2283324.n4.nabble.com/template/NamlServlet.jtp?macro= > unsubscribe_by_code&node=2341805&code=YXJ0QGFtbGludi5jb218MjM0MTgwNXwy > MDc3NjQwODU5> > . > NAML > <http://activemq.2283324.n4.nabble.com/template/NamlServlet.jtp?macro= > macro_viewer&id=instant_html%21nabble%3Aemail.naml&base=nabble.naml.na > mespaces.BasicNamespace-nabble.view.web.template.NabbleNamespace-nabbl > e.view.web.template.NodeNamespace&breadcrumbs=notify_subscribers%21nab > ble%3Aemail.naml-instant_emails%21nabble%3Aemail.naml-send_instant_ema > il%21nabble%3Aemail.naml> > -- View this message in context: http://activemq.2283324.n4.nabble.com/Need-Help-With-A-JMS-Exception-tp4716045p4716067.html Sent from the ActiveMQ - User mailing list archive at Nabble.com.
