failing when sending a command via MQTT

ChirpStack Application Server
1

Hi, I have been stuck trying to send commands via mosquitto_pub.
I have a notebook/server with Ubuntu server where I install chirpstack and chirpstack gateway bridge, for the gateway, I am using the Dragino DLOS8, and for a node, a Dragino LT-22222-L which has a relay output.

I can send commands to the LT-22222-L from the WebUI without a problem, but nothing happens when I try to send commands via mosquitto_sub.

I get into the server via SSH and I use mosquitto_sub -d -h localhost -p 1883 -t '#' to “see” what is going on with the commands when I send a command from the WebUI, it shows messages from the topic au915_2/gateway/a84041ffff252c08/command/down

to send a command via mosquitto_sub, first, I get into the notebook/server via SSH from another terminal and then I use mosquitto_pub -d -h localhost -p 1883 -t "application/861cbd58-9d39-4046-a074-b6d47e40dec7/device/a8404152d185b432/command/down" -m "{ "devEui": "a8404152d185b432", "confirmed": true, "fPort": 10, "data": "AwEA" }", with this action i get this output from the other terminal Client (null) received PUBLISH (d0, q0, r0, m0, 'application/861cbd58-9d39-4046-a074-b6d47e40dec7/device/a8404152d185b432/command/down', ... (68 bytes)) { devEui: a8404152d185b432, confirmed: true, fPort: 10, data: AwEA } but no action is made from the node.

the only modification that I made to the chirpstack-gateway-bridge.toml file is that the marshaler is set to “json” so the output of the MQTT messages is readable

any comment is welcome.

2

After triggering:

mosquitto_pub -d -h localhost -p 1883 -t "application/861cbd58-9d39-4046-a074-b6d47e40dec7/device/a8404152d185b432/command/down" -m "{ "devEui": "a8404152d185b432", "confirmed": true, "fPort": 10, "data": "AwEA" }"

And monitoring your MQTT broker is there post to au915_2/gateway/a84041ffff252c08/command/down like when using the UI?

3

There was no post like when WebUI just the message, but I kept trying with the mosquitto_pub command, and it turned out it was a problem formatting the message.

mosquitto_pub -h localhost -p 1883 -t 'application/861cbd58-9d39-4046-a074-b6d47e40dec7/device/a8404152d185b432/command/down' -m '{"devEui":"a8404152d185b432","confirmed":true,"fPort":5,"data":"AwAA"}'

This command works without a problem. Both the topic and the message need to be in single quotation marks(’ '), but inside the JSON, they need to be in double quotation marks(" ").