DevOps

Monitor Fly.io with MrCron

MrCron tracks Fly.io app and machine state every 5 minutes so you can catch zero-running-machine outages and stopped apps before your users do.

How MrCron monitors Fly.io

  • App count across your Fly.io organization.
  • Machine running and stopped counts per app.
  • Alert on any app with zero running machines.
  • Auth-failure detection with an amber Rotate key CTA when the API token stops working.
  • Alert rules that fire on machine state changes via any notification channel.

What you will see

Apps + machines running/stopped counts + zero-running-machine alerts.

Auth flow: API Key. Credentials are stored encrypted at rest with AES-256-GCM and never returned to your browser.

Start monitoring Fly.io

Sign in, create a project, and connect Fly.io in under a minute. First check ships in the free tier.

Start monitoring Fly.io

Frequently asked questions

What Fly.io credentials does MrCron need?
A Fly.io API token from flyctl auth token. MrCron stores it encrypted at rest and only decrypts it inside the sync worker.
Does MrCron support multiple Fly.io orgs?
Yes. Attach one Fly.io integration per project; each carries its own API token and org scope.
What counts as a stopped machine?
MrCron uses the Fly machine state field. STARTED counts as running; STOPPED, SUSPENDED, DESTROYING, and any non-running state counts as stopped.
Can I alert on a specific app going to zero machines?
Yes. Create an alert rule on the app's machine running count and set the threshold at 0. Route to any notification channel.
Want the full concept-level detail? See MrCron docs for how projects, checks, and sync cadence work.