HTTP 421 Misdirected Request

The request was sent to a server that cannot produce a response for the target authority.

Use 421 for connection reuse or HTTP/2 routing situations where the request authority is wrong.

httpstatus codehttp2routing

Response (http)

HTTP/1.1 421 Misdirected Request

Use 421 for connection reuse or HTTP/2 routing situations where the request authority is wrong.

Common mistakes

Reusing a connection for an authority the server cannot serve, or using 421 for ordinary application routing failures.

Registry reference: RFC9110, Section 15.5.20

Sources