500-599
Server error responses
<500/> Internal Server Error
An unspecified internal server error
Official Substatus codes
<501/> Not Implemented
currently not implemented
Official
<502/> Bad Gateway
the downstream server returned an error message
Official Substatus codes
<503/> Service Unavailable
the service is not available
Official Substatus codes
<504/> Gateway Timeout
The parent server did not respond in a timely manner
Official
<506/> Variant Also Negotiates
Endpoint negotiates itself
Official
<507/> Insufficient Storage
no memory available
Official
<508/> Loop Detected
Loop detected
Official
<510/> Not Extended
expectation was not met
Official
<511/> Network Authentication Required
network authentication was expected
Official
<520/> Web Server Returned an Unknown Error
the origin server has returned an empty, unknown or unexpected response to Cloudflare
Unofficial (Cloudflare)
<521/> Web Server Is Down
The origin server has rejected connections from Cloudflare
Unofficial (Cloudflare)
<522/> Connection Timed Out
Cloudflare has stopped contacting the origin server
Unofficial (Cloudflare)
<523/> Origin Is Unreachable
Cloudflare could not reach the origin server
Unofficial (Cloudflare)
<524/> A Timeout Occurred
Cloudflare was able to establish a TCP connection to the origin server
Unofficial (Cloudflare)
<525/> SSL Handshake Failed
Cloudflare could not negotiate an SSL/TLS handshake with the origin server
Unofficial (Cloudflare)
<526/> Invalid SSL Certificate
Cloudflare konnte das SSL-Zertifikat auf dem Ursprungs-Webserver nicht validieren
Unofficial (Cloudflare)
<527/> Railgun Error
Connection between Cloudflare and the Railgun server interrupted
Unofficial (Cloudflare)