unknown_collector_source

Summary

unknown collector source `{0}` for metric `{1}`

Help

no collector named {0} is configured; check the [[collectors]] entries

Details

When this fires

A rule used a fully qualified selector like mybox.cpu.usage (collector name, then metric) and the mybox part doesn't match any configured [[collectors]].name. nanook check underlines the source qualifier in your TOML so you can see exactly which token is unknown.

What to check

The qualifier matches [[collectors]].name, not kind. To match any collector of a given kind, drop the qualifier and use the bare metric.

[[collectors]]
name = "mybox"   # this is what selectors quote
kind = "cpu"

Then in a rule:

expr = "mybox.cpu.usage > 80%"