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Electronic Theatre Controls Inc

How to configure the MQTT Broker to allow external (other Computers / Devices / Sensors) access

If your Syrcadia System is using 3rd Party Sensors or Data Sources, the data needs to get into the Syrcadia Software.

This is done via a Protocol called MQTT.
MQTT needs a "MQTT broker" to function

An MQTT broker is basically a kind of centralised storage place
where every Data Source can deliver data to
and every data consumer will get notified about a change or can ask for this data

Syrcadia allows for an MQTT broker called Mosquitto to be installed on the PC and Syrcadia (and other data sources such as sensors) can use this broker.
It is also possible to use a different broker on a different machine / IP address.

However, for security reasons the Mosquitto broker installed on a PC does not allow a connection for devices from the network (only connection from the same machine is allowed).

In order for sensors to deliver their data to the MQTT broker on the PC, this default restriction needs to be modified.

In order to do so, follow these steps:

  • Find the file: mosquitto.conf on your PC (this is usually located in C:\program files\mosquitto)
  • Open up this file in a text editor (in administrator mode)
  • Scroll down to  the LISTENERS section
  • Sections will be designated like this :

#  ========================
#   Listeners
# =========================

  • (commented lines have a # at the start and  Un-commented  do not.)
  • In the LISTENERS section, find the commented line: #Listener , then un-comment and modify to: listener 1883
  • Scroll down till you see  the SECURITY section
  • In the SECURITY section, find the line: # allow_anonymous true  un-comment and modify to: allow_anonymous true
  • Save the file and re-start the PC
  • Configure the Sensor to use a broker with the IP address of the PC, and configure a topic structure that is in sync with the chosen Syrcadia sensor topics
  • Sensors should now be able to connect and share their data using this broker.
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