MQTT

The dsmr_mqtt process

Since DSMR-reader v4.x, you no longer need to manually configure dsmr_mqtt. It has been merged with dsmr_backend.

It should be already configured while installing or upgrading DSMR-reader and listed running if you execute sudo supervisorctl status. Make sure that dsmr_backend is running.

MQTT caching

MQTT messages are:

  • Sent with the retain flag, asking the broker to cache the latest value sent to each topic.
  • Cached for an hour, to reduce the number of duplicate messages sent.
  • Discarded when there is already another unsent message queued with the exact same topic and contents.

This prevents duplicate messages and removes a significant overhead.