HTTP 1xx

101 Switching Protocols

The server is switching protocols as requested, for example upgrading to a WebSocket connection.

1xx Informational

What causes it

  • A client requested a protocol upgrade with the Upgrade header.

How to fix it

Expected during WebSocket handshakes. No action needed.

Example response

A typical raw HTTP response a client receives for a 101, with the headers this code is defined around.

HTTP/1.1 101 Switching Protocols

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