HTTP 101 Switching Protocols vs 505 HTTP Version Not Supported
HTTP 101 (Switching Protocols) is a 1xx Informational response, while 505 (HTTP Version Not Supported) is a 5xx Server Error response. 101 indicates that the server understands the Upgrade header field request and indicates which protocol it is switching to. In contrast, 505 means that the server does not support the HTTP version used in the request.
説明
The server understands the Upgrade header field request and indicates which protocol it is switching to.
このコードが表示される場合
When upgrading from HTTP/1.1 to WebSocket, or to HTTP/2.
解決方法
This is normal behavior during protocol upgrades. Ensure your client supports the target protocol.
説明
The server does not support the HTTP version used in the request.
このコードが表示される場合
When a client uses an HTTP version the server doesn't support.
解決方法
Use a supported HTTP version (typically HTTP/1.1 or HTTP/2).
主な違い
101 is a 1xx Informational response, while 505 is a 5xx Server Error response.
HTTP 101: The server understands the Upgrade header field request and indicates which protocol it is switching to.
HTTP 505: The server does not support the HTTP version used in the request.
You encounter 101 when when upgrading from HTTP/1.1 to WebSocket, or to HTTP/2.
You encounter 505 when when a client uses an HTTP version the server doesn't support.
どちらをいつ使うか
For 101 (Switching Protocols): This is normal behavior during protocol upgrades. Ensure your client supports the target protocol. For 505 (HTTP Version Not Supported): Use a supported HTTP version (typically HTTP/1.1 or HTTP/2).