HTTP 421 Misdirected Request

What is HTTP 421 Misdirected Request?

The 421 (Misdirected Request) status code indicates that the request was directed at a server that is not able to produce a response. This can occur when a connection is reused for a different origin in HTTP/2 or when a server receives a request for a virtual host it does not serve.

Common Use Cases

• HTTP/2 connection reuse for different origins
• Load balancer routing errors
• Misconfigured virtual hosts

# Nginx - handling misdirected requests
server {
    listen 443 ssl http2;
    server_name example.com;
    
    if ($host != 'example.com') {
        return 421;
    }
}