18.3. Guarantees of Non-Transactional Acknowledgments

If you are acknowledging the delivery of a message on the client side using a non transacted session, HornetQ can be configured to block the call to acknowledge until the acknowledge has definitely reached the server, and a response has been sent back to the client. This is configured with the parameter BlockOnAcknowledge. If this is set to true then all calls to acknowledge on non-transacted sessions will block until the acknowledge has reached the server, and a response has been sent back. You might want to set this to true if you want to implement a strict at most once delivery policy. The default value is false