HTTP 103 Early Hints vs 520 Web Server Returned an Unknown Error
HTTP 103 (Early Hints) is a 1xx Informational response, while 520 (Web Server Returned an Unknown Error) is a 5xx Server Error response. 103 indicates that used to return some response headers before the final HTTP message. Allows the browser to start preloading resources while the server prepares the response. In contrast, 520 means that cloudflare-specific. The origin server returned an unexpected response that Cloudflare could not process.
Description
Used to return some response headers before the final HTTP message. Allows the browser to start preloading resources while the server prepares the response.
Quand vous le voyez
When a server wants the browser to start loading CSS/JS before the full response is ready.
Comment résoudre
No fix needed. This optimization helps speed up page loading.
Description
Cloudflare-specific. The origin server returned an unexpected response that Cloudflare could not process.
Quand vous le voyez
When Cloudflare receives an empty, unknown, or malformed response from the origin.
Comment résoudre
Check origin server logs. Ensure responses include proper headers. Verify SSL configuration.
Différences clés
103 is a 1xx Informational response, while 520 is a 5xx Server Error response.
HTTP 103: Used to return some response headers before the final HTTP message. Allows the browser to start preloading resources while the server prepares the response.
HTTP 520: Cloudflare-specific. The origin server returned an unexpected response that Cloudflare could not process.
You encounter 103 when when a server wants the browser to start loading CSS/JS before the full response is ready.
You encounter 520 when when Cloudflare receives an empty, unknown, or malformed response from the origin.
Quand utiliser lequel
For 103 (Early Hints): No fix needed. This optimization helps speed up page loading. For 520 (Web Server Returned an Unknown Error): Check origin server logs. Ensure responses include proper headers. Verify SSL configuration.