5xx Server errors · Cloudflare (not part of the HTTP standard)
522 Connection Timed Out
Cloudflare's connection to the origin server timed out.
Common causes
- The origin is overloaded or offline.
- Network problems or a firewall dropping packets.
How to fix it
- Check the origin is online and not overloaded.
- Check firewalls aren't silently dropping Cloudflare's connections.
Find out the moment your site returns 522
Spot Downtime monitors count this as down and alert you, since visitors see an error. (The public “Is it down?” checker treats 4xx answers from big sites as online, because many refuse automated requests.)