Get external IP of a server machine in PHP

1. $externalContent = file_get_contents('http://checkip.dyndns.com/');
   preg_match('/Current IP Address: \[?([:.0-9a-fA-F]+)\]?/', $externalContent, $m);
   $externalIp = $m[1];
   //AppleConnect Configuration
   $sugar_config['AppleConnectIpKey'] = $externalIp;  
2. 
   
3. 
   
4.   
5.