Testing a lot around Grafana Alerting and I might design something wrong here…
My use-case : Monitoring hundreds of energy meters.
Designing a Grafana Alert for sudden voltage change, high current, low frequency… is quite easy and is heavily used in our context !
But how to detect a missing energy meter which stopped responding and sending data ?
Grafana “No Data” alerting seems to be like an All-or-nothing parameter that fire an alarm when you don’t have any incoming data from your query.
Using dashboard variables, and row repeat or panel repeat for each energy meter is not a solution because when creating the alert from the panel, the query is a “Select data from all energy meters” so you won’t notice any change in the number of alive energy meters nor identify who is the missing one…
How to design a query that would look like : “select hostname(s) that were present in the last 24h but are absent from the last 10 minutes ?”
Any help/hints/advices welcomed here