Example : https://www.cloudmqtt.com/docs/alarms.htmlReef-pi is designed to run even without any network, so not having network is not an issue for reef-pi as long as you are not using network based drivers.
For the use case you are referring , it’s commonly known as external monitoring. I know adafruit has something called trigger that can notify you if reef-pi stops sending data. That will exactly what a typical external monitoring would do. If there’s a public Mqtt service we can do that with mqtt based metrics as well, since 4.0 release. In all these cases you need an externally hosted service /cloud like thing




