Question

I want a PHP script which allows you to ping an IP address and a port number (ip:port). I found a similar script but it works only for websites, not ip:port.

<?php

function ping($host, $port, $timeout) 
{ 
  $tB = microtime(true); 
  $fP = fSockOpen($host, $port, $errno, $errstr, $timeout); 
  if (!$fP) { return "down"; } 
  $tA = microtime(true); 
  return round((($tA - $tB) * 1000), 0)." ms"; 
}

//Echoing it will display the ping if the host is up, if not it'll say "down".
echo ping("www.google.com", 80, 10);

?>

I want this for a game server.

The idea is that I can type in the IP address and port number, and I get the ping response.

Answer 1

I think the answer to this question pretty much sums up the problem with your question.

If what you want to do is find out whether a given host will accept
TCP connections on port 80, you can do this:

$host = '193.33.186.70'; 
$port = 80; 
$waitTimeoutInSeconds = 1; 
if($fp = fsockopen($host,$port,$errCode,$errStr,$waitTimeoutInSeconds)){   
   // It worked 
} else {
   // It didn't work 
} 
fclose($fp);

For anything other than TCP it will be more difficult (although since
you specify 80, I guess you are looking for an active HTTP server, so
TCP is what you want). TCP is sequenced and acknowledged, so you will
implicitly receive a returned packet when a connection is successfully
made. Most other transport protocols (commonly UDP, but others as
well) do not behave in this manner, and datagrams will not be
acknowledged unless the overlayed Application Layer protocol
implements it.

The fact that you are asking this question in this manner tells me you
have a fundamental gap in your knowledge on Transport Layer protocols.
You should read up on ICMP and TCP, as well as the OSI Model.

Also, here’s a slightly cleaner version to ping to hosts.

// Function to check response time
function pingDomain($domain){
    $starttime = microtime(true);
    $file      = fsockopen ($domain, 80, $errno, $errstr, 10);
    $stoptime  = microtime(true);
    $status    = 0;

    if (!$file) $status = -1;  // Site is down
    else {
        fclose($file);
        $status = ($stoptime - $starttime) * 1000;
        $status = floor($status);
    }
    return $status;
}