HTTP 103 Early Hints vs 503 Service Unavailable
HTTP 103 (Early Hints) is a 1xx Informational response, while 503 (Service Unavailable) 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, 503 means that the server is temporarily unable to handle the request due to maintenance or overload. Should include a Retry-After header.
Описание
Used to return some response headers before the final HTTP message. Allows the browser to start preloading resources while the server prepares the response.
Когда вы это видите
When a server wants the browser to start loading CSS/JS before the full response is ready.
Как исправить
No fix needed. This optimization helps speed up page loading.
Описание
The server is temporarily unable to handle the request due to maintenance or overload. Should include a Retry-After header.
Когда вы это видите
During maintenance windows, server overload, or when the application pool is exhausted.
Как исправить
Wait and retry. Check the Retry-After header. Scale up servers if it's a capacity issue.
Ключевые различия
103 is a 1xx Informational response, while 503 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 503: The server is temporarily unable to handle the request due to maintenance or overload. Should include a Retry-After header.
You encounter 103 when when a server wants the browser to start loading CSS/JS before the full response is ready.
You encounter 503 when during maintenance windows, server overload, or when the application pool is exhausted.
Когда что использовать
For 103 (Early Hints): No fix needed. This optimization helps speed up page loading. For 503 (Service Unavailable): Wait and retry. Check the Retry-After header. Scale up servers if it's a capacity issue.