Can I perform a DNS lookup (hostname to IP address

Question

I would like to use client-side Javascript to perform a DNS lookup (hostname to IP address) as seen from the client's computer. Is that possible?

Answer 1

The hosted JSONP version works like a charm, but it seems it goes over its resources during night time most days (Eastern Time), so I had to create my own version.

This is how I accomplished it with PHP:

<?php
header('content-type: application/json; charset=utf-8');

$data = json_encode($_SERVER['REMOTE_ADDR']);
echo $_GET['callback'] . '(' . $data . ');';
?>

Then the Javascript is exactly the same as before, just not an array:

<script type="application/javascript">
function getip(ip){
    alert('IP Address: ' + ip);
}
</script>

<script type="application/javascript" src="http://www.anotherdomain.com/file.php?callback=getip"> </script>

Simple as that!

Side note: Be sure to clean your $_GET if you're using this in any public-facing environment!