Hello,
I was wondering if someone could assist in an issue I am having trying to configure JNDI topics to use a DeadEvent queue when a persistent message TTL expires.
We are currently using UM 9.10
I have created a JNDI Mixed topic with a Dead Event queue configured.
I’ve also successfully published messages to it with webMethods.
The messages have are set to persistent with a TTL of 5000 (5 seconds) for testing.
I have also set up a JMS trigger have confirmed that the messages are being subscribed. The named object message counter is also incrementing so I know the “AUTO_ACK” setting on the trigger it working.
However, the message then moves to the DeadEvent queue as well.
Based on the documentation I was assuming the message would only go to the dead event queue only is no client subscribed to the message within the TTL.
Am I missing something? If there is another discussion topic on here that already talk about this I apologize.
Thanks,
Matthew Falcone
My previous statements in one of similar topics, see if that helps:
The dead letter queue behaviour is slight different in UM as compared to Broker, as per the wiki, Dead letter queue - In message queueing the dead letter queue is a service implementation to store messages that meet one or more of the following criteria :
Message that is sent to a queue that does not exist.
Queue length limit exceeded.
Message length limit exceeded.
Message is rejected by another queue exchange.
Message reaches a threshold read counter number, because it is not consumed. Sometimes this is called a “back out queue”.
As per the above information you can set a TTL or Capacity Params on Channel/Topic with Honour Capacity=true by default. If the messages are not consumed by the subscriber within the TTL the messages will then go to DES channel which can be subscribed by the trigger and process these messages.
However, as per the dead letter queue does not work in UM if there is no intended active subscriber on a channel or topic with TTL=0 and Capacity=0, it still stays in the main channel/topic and do not move to DES channel.
Product team can provide more information on this. But there are some fixes and enhancements done in UM 10.0 release. Please check the documentation for more details.