[SOLVED] How to configure certificates for Grafana MQTT plugin to connect to HiveMQ cloud broker

How to configure certificates for Grafana MQTT plugin to connect to HiveMQ cloud broker

I'm running Grafana 9.3.6 installed via apt-get on Ubuntu 20.04.5

I have a HiveMQ cloud broker I'm trying to connect to. Previously I succeeded to connect via mosquitto command line tool and mosquittopp C++ interface. These required me to provide a certificate or certificate path.

I used the .pem file provided by HiveMQ with the command line tool.
I provided the /etc/ssl/certs/ path for the C++ interface (the 1st option did not work out)

Now I'm trying to connect via the Grafana MQTT plugin. I installed it using

grafana-cli plugins install grafana-mqtt-datasource.

When trying to add it in the web gui, I get the following error:

error connecting to MQTT broker: network Error : EOF

I can see some messages going back and forth in Wireshark so I assume the problem is with the certificates.

I tried editing the grafana.ini file without success. It's not completely clear which file/path should I add where and what other options I need to set.

Edit: the grafana.ini file had nothing to do with this.

Solution

As @hardillb pointed out, I had to pay attention to the URL scheme. After putting tls:// in front of the broker URL as described in grafana-mqtt-datasource, everything worked.