Hi David, it's all configured in your "redeliveryPolicy", where you instructed the broker to try resending the message indefinitely.
See http://activemq.apache.org/message-redelivery-and-dlq-handling.html for more information how redelivery works and how you can use "Dead letter queues" Cheers -- Dejan Bosanac - http://twitter.com/dejanb Open Source Integration - http://fusesource.com/ ActiveMQ in Action - http://www.manning.com/snyder/ Blog - http://www.nighttale.net On Sat, Nov 7, 2009 at 7:35 PM, David Erickson <deric...@stanford.edu>wrote: > > Hi All, > I am using AMQ inside a Spring IoC container. It is a very simple setup > with the following config: > > <!-- ActiveMQ Broker --> > <amq:broker useJmx="false" persistent="false"> > <amq:transportConnectors> > <amq:transportConnector uri="tcp://localhost:0" /> > </amq:transportConnectors> > > </amq:broker> > > <!-- ActiveMQ destinations to use --> > <amq:queue id="mailDestination" physicalName="mailsender"/> > > <!-- JMS ConnectionFactory to use, configuring the embedded broker using > XML --> > <amq:connectionFactory id="jmsFactory" brokerURL="vm://localhost"> > <amq:redeliveryPolicy> > <amq:redeliveryPolicy backOffMultiplier="2" > useExponentialBackOff="true" initialRedeliveryDelay="1000" > maximumRedeliveries="-1"/> > </amq:redeliveryPolicy> > </amq:connectionFactory> > > <bean id="myJmsTemplate" class="org.springframework.jms.core.JmsTemplate"> > <property name="connectionFactory"> > <!-- lets wrap in a pool to avoid creating a connection per send --> > <bean class="org.apache.activemq.pool.PooledConnectionFactory"> > <property name="connectionFactory"> > <ref local="jmsFactory"/> > </property> > </bean> > </property> > <property name="pubSubDomain"> > <value>false</value> > </property> > </bean> > > <bean id="mailContainer" > class="org.springframework.jms.listener.DefaultMessageListenerContainer"> > <property name="connectionFactory" ref="jmsFactory"/> > <property name="destination" ref="mailDestination"/> > <property name="messageListener" ref="mailConsumer"/> > <property name="sessionTransacted" value="true"/> > </bean> > > Along with one corresponding producer and consumer. > > My question is this, I noticed that my consumer was having problems sending > one of the emails in the queue, it was throwing an exception, being placed > back in the queue, then the entire queue was waiting the backoff time for > this message to attempt to be delivered again, over and over again, > producing a head of line blocking problem (no messages can be delivered > until the one with the error is delivered). > > Is there a solution for this? Can the message that failed be pushed to a > re-delivery queue, or a troubled queue rather than the main queue? Or can > the consumer walk through the queue looking for a message that is ready to > be delivered rather than blocking on the front message that isn't set to be > delivered for some long amount of time because of a previous failure and > backoff time? > > Thanks! > -- > View this message in context: > http://old.nabble.com/Message-Head-of-line-blocking-tp26247283p26247283.html > Sent from the ActiveMQ - User mailing list archive at Nabble.com. > >
