Hi all, I am using Active MQ 5.14.3 as an MQTT broker. I am talking to it using the paho java client v1.1.1.
My application uses a paho MQTT client to subscribe to a certain topic. I am also setting manual acks so when it gets a callback (each time a msg arrives) it does not ack immediately the msg (QOS 1 or 2). I pass the message further along for processing and only after the processing is done I ack back the message (based on the initial id). In the logs I am seeing a lot of messages being resent by the broker (the callback is called with the same messages). I am assuming this happens because my processing is taking longer than some redelivery timeout on the broker. It seems to happen alternatively between 1 and 2 seconds. Questions: 1. Is this redelivery timeout specified by MQTT or ActiveMQ? I could not find explicit mention of it in the MQTT specs. 2. What is that redelivery timeout and where is it specified? 3. How to make sure that the redeliveries I am seeing are due indeed to timeout on the broker and not something else? What I tried: I applied the config suggested here http://activemq.apache.org/message-redelivery-and-dlq-handling.html to set the redeliver timeout. It did not seem to work. I set the redelivery delay to every 10 sec but it actually redelivers every 1-2 sec like before. Here is the config I started ActiveMQ with. The stuff is bold is what I added extra to the default ActiveMQ config: <broker xmlns="http://activemq.apache.org/schema/core" brokerName="localhost" dataDirectory="${activemq.data}" *schedulerSupport="true"*> * <plugins>* * <redeliveryPlugin fallbackToDeadLetter="true"* * sendToDlqIfMaxRetriesExceeded="true">* * <redeliveryPolicyMap>* * <redeliveryPolicyMap>* * <defaultEntry>* * <!-- the fallback policy for all other destinations -->* * <redeliveryPolicy maximumRedeliveries="-1"* * initialRedeliveryDelay="5000"* * redeliveryDelay="10000"/>* * </defaultEntry>* * </redeliveryPolicyMap>* * </redeliveryPolicyMap>* * </redeliveryPlugin>* * </plugins>* ... </broker> Any help would be much appreciated, M