Check IP

$_SERVER['REMOTE_ADDR'] =
2600:1f28:365:80b0:5d3a:68c2:da92:bb87

$_SERVER['HTTP_X_FORWARDED_FOR'] =
2600:1f28:365:80b0:5d3a:68c2:da92:bb87

Check IP service (use with for example pfSense DDNS)