How long can a instance run without restarting?

I want to run a Docker container that has a few daemons/background processes running inside of it, but no web server.

Is it possible to deploy it to a single Fly.io instance with a disk volume?

Is there a guaranteed uptime, or will you suddenly reboot instances with no warning (on the assumption they are stateless)?

One of the processes may need to run for weeks uninterrupted without a reboot. Is this possible?

Yes, long running VMs without a web service are supported. Just remove the [services] block from your fly.toml.

There’s no strict uptime guaranty, but these should be pretty stable. It is more likely a VM on Fly shuts down than one at, say, DigitalOcean. But we don’t systemically turn VMs off.

VMs will shut down when:

  1. Hardware fails
  2. If there are extreme capacity issues in a region, larger VMs get priority (this has happened once, ever).

Your processes can definitely run for weeks. You can also set kill_timeout to give some control over shut down if we ever deliberately turn a VM off.