503 Service Unavailable
The server is currently unable to handle the request due to a temporary overload or scheduled maintenance, which will likely be alleviated after some delay.
The server MAY send a Retry-After header field1 to suggest an appropriate amount of time for the client to wait before retrying the request.
Note: The existence of the 503 status code does not imply that a server has to use it when becoming overloaded. Some servers might simply refuse the connection.
- 1 Retry-After RFC7231 Section 7.1.3
- Source: RFC7231 Section 6.6.4
503 Code References
-
.NET HTTP Status Enum
HttpStatusCode.ServiceUnavailable -
Rust HTTP Status Constant
http::StatusCode::SERVICE_UNAVAILABLE -
Rails HTTP Status Symbol
:service_unavailable -
Go HTTP Status Constant
http.StatusServiceUnavailable -
Symfony HTTP Status Constant
Response::HTTP_SERVICE_UNAVAILABLE -
Python2 HTTP Status Constant
httplib.SERVICE_UNAVAILABLE -
Python3+ HTTP Status Constant
http.client.SERVICE_UNAVAILABLE -
Python3.5+ HTTP Status Constant
http.HTTPStatus.SERVICE_UNAVAILABLE
