[Cloudflare outage] Apps were inaccessible for 40 minutes returning 520 or 500 errors

Our apps in AMS region were inaccessible for about 40 minutes. 6:30 to 7:09 UTC

Domains are routed via Cloudflare. Browser showed either nginx 500 internal server error or Cloudflare 520 host error. There are no issues in app logs. Apps were accessible via *.fly.dev

What was the issue and how to mitigate it in the future?

Honeybadger monitor:
image

Looks like a Cloudflare issue:

1 Like

Oh, thanks! Nginx error made me think it was Fly edge