Tuning a Noisy Prometheus Alert Without Missing Real Outages

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A common scenario is an alert that wakes an on-call engineer for brief service blips that resolve on their own, which risks the engineer ignoring a genuine outage later. The recommended fix starts by reviewing recent pages to find the single most frequent alert that required no action, then measuring how long those incidents typically lasted. Next, the engineer decides the shortest outage worth being paged for, such as one lasting more than five minutes. Adding a 'for' duration to the Prometheus rule then keeps the alert pending until the condition persists, filtering out short blips while still catching real failures. For flapping services, a 'keep_firing_for' setting can be added, and the change should be documented so future teams understand the reasoning.

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ProgrammingDEV Community ·

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