HTTP 101 Switching Protocols vs 406 Not Acceptable
HTTP 101 (Switching Protocols) is a 1xx Informational response, while 406 (Not Acceptable) 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, 406 means that the server cannot produce a response matching the Accept headers sent by the client.
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 cannot produce a response matching the Accept headers sent by the client.
このコードが表示される場合
When requesting a content type the server doesn't support (e.g., Accept: application/xml when only JSON is available).
解決方法
Adjust the Accept header to a format the server supports.
主な違い
101 is a 1xx Informational response, while 406 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 406: The server cannot produce a response matching the Accept headers sent by the client.
You encounter 101 when when upgrading from HTTP/1.1 to WebSocket, or to HTTP/2.
You encounter 406 when when requesting a content type the server doesn't support (e.g., Accept: application/xml when only JSON is available).
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 406 (Not Acceptable): Adjust the Accept header to a format the server supports.