500-599

Server error responses

The HTTP status codes in the range from 500 to 599 are server error codes. They are used by the server to tell the client that an error has occurred that prevented the request from being processed. These codes indicate that an error occurred that prevented the request from being processed. They are commonly used by web applications and APIs to indicate problems on the server. It is important to note that some of these codes can also help the client diagnose and fix the error. For example, the 500 code indicates that an internal server error has occurred, while the 503 code indicates that the server is currently unavailable. This information can help the client decide whether to resend the request or wait until the server is available again.

<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)

<530/> Error 530

HTTP error 530 is returned and a 1XXX error is displayed
Unofficial (Cloudflare)