HTTP 444 No Response (Nginx)

Overview

The HTTP 444 No Response status code is not specified in the HTTP/1.1 standard but is often used to indicate that the server has returned no information to the client and closed the connection. This status code is non-standard and specific to certain web servers.

Purpose

The HTTP 444 status code is typically used to indicate that the server did not send any response to the client, and the connection was closed abruptly. It may be implemented by certain web servers as a way to handle situations where a response is not provided.

Usage

Server Behavior:

1. No Response Sent: The server does not send any response to the client.
2. Connection Closed: The server closes the connection abruptly without providing further information.

Scenarios

• Server Handling Unusual Conditions: Used when the server decides not to send any response to the client and closes the connection.

Curl Request and Response Example

Sending a request to a server that implements HTTP 444:

curl -i http://example.com/resource
# Expected behavior: Connection closed without receiving a response.

PHP cURL Request and Response Example

PHP script using cURL to handle a situation where the server sends HTTP 444:

<?php
$ch = curl_init('http://example.com/resource');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$response = curl_exec($ch);
if (curl_getinfo($ch, CURLINFO_HTTP_CODE) == 444) {
    echo "No Response";
}
curl_close($ch);
?>

Python Request and Response Example

Python script to handle a situation where the server sends HTTP 444:

import requests
response = requests.get('http://example.com/resource')
if response.status_code == 444:
    print("No Response")

Apache Configuration for HTTP 444 No Response

Configuring Apache to return HTTP 444 for specific conditions:

<VirtualHost *:80>
    ServerName example.com
    # Additional configurations as needed
    # ...
</VirtualHost>

<IfModule mod_rewrite.c>
    RewriteEngine On
    RewriteCond %{SOME_CONDITION_TO_RETURN_444}
    RewriteRule ^ - [R=444,L]
</IfModule>

NGINX Configuration for HTTP 444 No Response

Setting up NGINX to return HTTP 444 for specific conditions:

server {
    listen 80;
    server_name example.com;
    # Additional configurations as needed
    # ...
    
    if (SOME_CONDITION_TO_RETURN_444) {
        return 444;
    }
}

HTTP 431 Request Header Fields Too Large HTTP 449 Retry With (Microsoft)