MQTT connection between multiple LMs

MQTT connection between multiple LMs #

Task #

Connect multiple LogicMachine controllers located in different subnets.

mqtt_scheme

1. Requirements #

Install MQTT broker app and MQTT client app on LM1.

Install MQTT client app on LM2.

2. Configure MQTT broker on LM1 #

Set up only encrypted communication and enable access control list (per-user and per-topic).

mqtt_broker_01

mqtt_broker_02

3. Set up users and topics in the MQTT broker app #

Create users for both LM1 and LM2.

mqtt_broker_03

4. Configure MQTT client on LM1 #

Set up communication and username/password as configured in the MQTT broker app.

  • Set IP address to 127.0.0.1
  • Enable Encrypted connection
  • Set Port to 8883

mqtt_client_01

mqtt_client_02

mqtt_client_03

5. Configure MQTT topic and select KNX objects on LM1 #

Set up topic name as configured in the MQTT broker app.

mqtt_client_04

mqtt_client_05

6. Configure MQTT client on LM2 #

Set up communication and username/password as configured in the MQTT broker app.

  • Set IP address to LM1 IP address
  • Enable Encrypted connection
  • Set Port to 8883

mqtt_client_06

mqtt_client_07

7. Configure MQTT topic and select KNX objects on LM2 #

Set up topic names as it is in MQTT broker app

mqtt_client_08

Result - LM1 and LM2 can now exchange object values via MQTT #

mqtt_communnication_01

mqtt_communnication_02

Further assistance can be found in this forum thread