MQ Connectivity retained messages

You can send retained messages between Eclipse Amlen and IBM® MQ by using the RetainedMessages parameter in a destination mapping rule.

The RetainedMessages parameter can be used to specify that either all the messages, or none of the messages, that are forwarded by using the destination mapping rule are forwarded as retained messages. This parameter overrides any settings from the original message publisher.

You can specify that all messages are retained messages only for destination mapping rules with a single queue manager connection. The destination mapping rule cannot be a rule that maps to an Eclipse Amlen queue, or a IBM MQ queue.

To clear retained messages that are sent between Eclipse Amlen and IBM MQ, you must clear the messages on both servers. To ensure that the retained message is not resent, first clear the message from the source of the destination mapping rule. Then, clear the message from the destination of the rule. You can delete an MQTT retained message from Eclipse Amlen by sending a retained message with a zero length payload. The message is delivered normally, and the current retained message is cleared. You can delete a retained message in IBM MQ by using the CLEAR TOPICSTR MQSC command. For more information about the CLEAR TOPICSTR command, see CLEAR TOPICSTR in the IBM MQ documentation.

For more information about configuring destination mapping rules, see Configuring destination mapping rules.