That's right, there will always be a chance of duplicate messages - hence the JMSRedelivered flag in the JMS specification itself.
Specifically responding to the use-case in question, the failover transport re-attempts message sends if they have not completed successfully on a prior attempt. If the broker already received the message, yes it will get duplicated. -- View this message in context: http://activemq.2283324.n4.nabble.com/Client-reaction-to-server-failure-tp4698426p4698967.html Sent from the ActiveMQ - User mailing list archive at Nabble.com.
