For Internal Port Scan from Web. Usually for security purpose db is not exposed to internet, it stays in the internal zones. So this will help in that case.

php-internal-port-scan-using-get-method

<?php
ini_set('max_execution_time', 0);
ini_set('memory_limit', -1);

if(!empty($_GET["ip"]) && !empty($_GET["port"])){
    $ip = $_GET["ip"];
    $port = $_GET["port"];

    //nginx Check
    $connection = @fsockopen($ip, $port, $errno, $errstr, 2);
    if (is_resource($connection)){
      fclose($connection);
      http_response_code(200);
    }else{
      http_response_code(404);
    }
} else{
    http_response_code(404);
}
?>