Patch Mod_RPAF / HostnameLookups

/etc/php.ini

auto_prepend_file = "/usr/lib/php/DNS_LOOKUP.php"


/usr/lib/php/DNS_LOOKUP.php

<?php
if(isset($_SERVER["REMOTE_HOST"])){
        exec('dig +time=2 +retry=0 +short -x ' . $_SERVER["REMOTE_ADDR"], $output);
        if (preg_match('#(.*).#i', implode("\n", $output), $host)){
                $_SERVER["REMOTE_HOST"]=$host[1];
        }
}