Gateway --- vs mosquitto what port to use in .json file?

I have a node that talks to my gateway and to the TTN. The global_conf.json file is set to port 1700. The gateway is a SEEED WM1302 on an RPi5. Now that I am transitioning to Chirpstack I installed the following pieces in docker and have them up and running:

My question is should I be changing the .json port to 1883? Does the MQTT server use port 1700 as it’s output to the gateway-bridge?

I am guessing that the WM1302 is nothing more than a conduit and has really no ports and that the 1700 lives on the Network Server at TTN…does this sound correct?


What is json port?

ChirpStack gateway bridge uses port 1700/UDP. It is Semtech packet forwarder.

Have you imstalled ChirpStack gateway bridge?

No json port…only json file that points to a port…the json file that lives on the WM1302 points to 1700. But according to documentation at Chirpstack this feeds MQQT…if you look at my attachment above you can see that the MQTT port looks like it expects data from port 1883…Hence the question should I change my json file to reflect 1883? somewhere along the way there is a port mismatch and I would like to know where to change it…

As far as the bridge question: yes once again the picture above reflects the processes running within the docker container…You can see tht the gateway-bridge is running…Here again the documentation leads me to believe that the flow of data will be UDP Packet Forwarder (which lives on my WM1302) to the MQTT server to Chirpstack-Gateway-Bridge and finally to Network Server (and down the road eventually info to get passed along as need to Application Server…The redis and postgresql containers are only running because the documentation suggested they needed to be installed.

My chirpstack-gateway-bridge.toml (section for the MQTT server):


My global_conf.json (gateway configuration section ): 

“server_address”: “localhost”,
“serv_port_up”: 1883,
“serv_port_down”: 1883,

My mosquitto.conf :

pid_file /run/mosquitto/

persistence true
persistence_location /var/lib/mosquitto/

log_dest file /var/log/mosquitto/mosquitto.log

include_dir /etc/mosquitto/conf.d



First of all, I’m not expert, but I think I could help a little bit
The chirpstack gateway bridge is (as the name implies) a bridge between the gateway (communicated trough UDP protocol) and the rest of the chirpstack stack (communicated trough MQTT protocol), so this component has 2 outputs and 2 inputs, an input and an output for UDP and another one for MQTT.
The MQTT is working on the port 1883 (by default) and the UDP input is on the port 1700 (by default)
So, if your gateway is sending the data in UDP protocol, and if you are not modifying the defaults ports of chirpstack, then you should send the data to the port 1700.