fail

Stopping on a state: fail

fail stops the collector on a state it alone knows, with a summary and a detail. Here, the software RAID of a Linux: no RAID, an empty answer, a lost disk.

How to read it

• fail('critical', 'A RAID array lost a disk', $mdstat['output']): the state, the summary, and an optional detail. Three states: - critical: the target is in trouble; - misconfigured: the probe is set wrong, here a host without software RAID; - unreachable: the target cannot be read.
• A stopped collector returns nothing, not even the values returned before the stop, and no watch is judged: the state of the probe is the one of fail.
• text.match($mdstat['output'], '[U*_[U_]*]') finds [U_] or [_UU]; list.count of the match is 0 when nothing matches.

To adapt it

• fail is for what the code alone knows. A threshold the administrator should set is a watch: here, the rebuilding of an array is a watch.state, that can be unchecked.
• A secret is never written in a summary or a detail: the validation refuses it.