HTTP 101 Switching Protocols vs 499 Client Closed Request
HTTP 101 (Switching Protocols) is a 1xx Informational response, while 499 (Client Closed Request) is a 4xx Client Error response. 101 indicates that the server understands the Upgrade header field request and indicates which protocol it is switching to. In contrast, 499 means that a non-standard status code used by Nginx when the client closes the connection before the server responds.
Description
The server understands the Upgrade header field request and indicates which protocol it is switching to.
Quand vous le voyez
When upgrading from HTTP/1.1 to WebSocket, or to HTTP/2.
Comment résoudre
This is normal behavior during protocol upgrades. Ensure your client supports the target protocol.
Description
A non-standard status code used by Nginx when the client closes the connection before the server responds.
Quand vous le voyez
In Nginx logs when clients timeout or navigate away before receiving the response.
Comment résoudre
Optimize server response times. Check for slow upstream services.
Différences clés
101 is a 1xx Informational response, while 499 is a 4xx Client Error response.
HTTP 101: The server understands the Upgrade header field request and indicates which protocol it is switching to.
HTTP 499: A non-standard status code used by Nginx when the client closes the connection before the server responds.
You encounter 101 when when upgrading from HTTP/1.1 to WebSocket, or to HTTP/2.
You encounter 499 when in Nginx logs when clients timeout or navigate away before receiving the response.
Quand utiliser lequel
For 101 (Switching Protocols): This is normal behavior during protocol upgrades. Ensure your client supports the target protocol. For 499 (Client Closed Request): Optimize server response times. Check for slow upstream services.