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Reliability Metrics

Downtime

Downtime is the time a service was unavailable during a period.

What is downtime?

Downtime describes the time a service was unavailable during a period. In reliability work, the label is useful only when it maps to a measurable check, a clear owner, and a next action when expectations break. Without that operational meaning, the phrase becomes decoration in dashboards and status updates.

Why it matters

Downtime matters because teams need a precise shared meaning for the time a service was unavailable during a period. Vague language turns incidents into arguments about words instead of fixes.

When everyone uses the same definition, alerts, status updates, and post-incident reviews stay aligned.

How it works

In practice, the time a service was unavailable during a period shows up as a concrete signal you can measure or communicate. Operators define what good looks like, watch for deviations, and record what happened when expectations break.

The useful version of downtime is operational: it changes who gets notified, what customers see, or which metric a team reviews after an incident.

Practical example

Imagine a team operating around 43 minutes of downtime in a month. When observed behavior stops matching the definition of downtime, the team treats that change as a reliability event with a clear owner and next step.

Common misconception

Downtime only counts when you post a status incident

That reading usually collapses distinct ideas into one slogan. Keep downtime tied to observable behavior so the definition stays useful under pressure.

How Fajita handles this

Define whether maintenance and missing data count before comparing downtime numbers.

Related documentation

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