522 Connection timed out
HTTP response status code 522 Connection timed out is an unofficial server error that is specific to Cloudflare. This HTTP status code occurs when Cloudflare is unable to connect to the origin server due to a timeout.
Usage
Cloudflare is a content delivery network that acts as a gateway between a user and a website server. When the 522 Connection timed out status code is received, Cloudflare attempted to connect to the origin server but was not successful due to a timeout. The HTTP Connection was not established most likely because the IP addresses of Cloudflare are blocked by the origin server, the origin server settings are misconfigured, or the origin server is overloaded.
Takeaway
The 522 Connection timed out status code is a Cloudflare-specific server error that is generated because Cloudflare unable to connect to the origin server and the HTTP Connection timed out.