Observability · Flashcard
An alert rule returns 3 series. How many alerts does it fire?
- AThree — one alert per returned label set, with its own state
- BOne — the rule is the alert, and the series are its evidence
- COne per rule group — related rules merge into one alert
- DNone until they agree — a rule needs a single clear result
Why this is the answer
An alerting rule creates one alert instance per series its expression returns, each carrying that series' labels, which is how a single rule pages separately for three broken instances. The rule is a template rather than the alert itself, groups control evaluation order rather than merging alerts, and multiple results are the normal case rather than an ambiguity.
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