Hi,
I just wanted to share an issue I have had and resolved, as it may help someone else in the future.
Last year I followed this awesome Grafana Blog article
and successfully had a few of my ESP32 Arduino boards sending metrics up to Prometheus in Grafana Cloud.
Unfortunately it stopped working some time earlier this year.
It turns out the issue (as far as I can tell) was that the Root CA Grafana uses changed. Now as the Arduino’s have pretty low processing capability compared to other devices, you have to hard code the Root CA of any SSL host you are talking to into the Arduino code.
So when Grafana Cloud’s Root CA changed, I needed to find the new one and update my code to have the new one in place of the old one.
One of the main libraries I use to allow an Arduino to talk to Grafana Cloud is Connection error · Issue #10 · grafana/prometheus-arduino · GitHub and there is an issue in the GitHub that I have updated with my solution.
So, please look there if you need to see how to work around the CA change until these libraries and their examples get updated.
Cheers,
PJ