[New date] We are going to start charging for dedicated IPv4 in ~~January 1st~~ starting February 1st

An update: We now allow having both a shared IPv4 and dedicated IPv4. This change should make it possible to switch to a shared IPv4 without downtime.

The produce looks like this:

  • Add shared ipv4 via flyctl ips allocate-v4 --shared
  • (Optional: add the shared ipv4 as an A record for your hostname if you don’t use a CNAME to .fly.dev)
  • Confirm your app works via shared IP: curl -Iv http://<your-hostname> --resolve <your-hostname>:80:<shared ipv4 you got> (should respond with a 301 redirect)
  • Wait for DNS caches to clear… probably 5 minutes but that varies wildly, this should be the biggest value between your DNS record’s TTL and our <your-app>.fly.dev record (300 I believe).
  • Remove the dedicated IPv4 from Fly (and optionally remove from your DNS if you set it manually as an A record)