Code 522

Connection timed out Cloudflare

Cloudflare failed to establish a TCP connection to the website hosted behind it. If Cloudflare does not get a SYN+ACK back within 15 seconds as part of the TCP handshake this error is returned.

sequenceDiagram participant User participant Cloudflare participant Website Note right of Website: Behind Cloudflare User ->> Cloudflare: Initial request Cloudflare ->>+ Website: Initiates TCP connection Cloudflare -->>+ Website: TCP connection fails Cloudflare -->> User: Returns 522 error