How to create distributed/mirrored dynamic scripting website (Step - 4 Region detection and redirection)

Step four: Region detection & redirection
First of all, download the latest database

wget software77.net/geo-ip/?DL=1 -O /path/IpToCountry.csv.gz

Create a table in your website database & import the data from the csv file

CREATE TABLE IF NOT EXISTS `ip2country` (  `start` int(10) unsigned NOT NULL DEFAULT '0',  `end` int(10) unsigned NOT NULL DEFAULT '0',  `registry` varchar(50) NOT NULL,  `assigned` varchar(50) NOT NULL,  `a2` char(2) NOT NULL DEFAULT '',  `a3` char(3) NOT NULL DEFAULT '',  `country` varchar(100) NOT NULL DEFAULT '',  PRIMARY KEY (`start`,`end`),  KEY `a2` (`a2`)) ENGINE=MyISAM DEFAULT CHARSET=utf8;LOAD DATA LOCAL INFILE 'YOUR_PATH/IpToCountry.csv' INTO TABLE ip2country FIELDS TERMINATED BY ',' ENCLOSED BY '"'  LINES TERMINATED BY '\n';

Now just need add a few line of php code at the beginning of index.php file to handle the redirect.

//If the visitor is search engine spider, then do not redirect.function check_if_spider(){	$spiders = array('Googlebot', 'Yammybot', 'Openbot', 'Yahoo', 'Slurp', 'msnbot', 'ia_archiver', 'Lycos', 'Scooter', 'AltaVista', 'Teoma', 'Gigabot', 'Googlebot-Mobile');	foreach ($spiders as $spider)	{		if (eregi($spider, $_SERVER['HTTP_USER_AGENT']))		{			return TRUE;		}	}	return FALSE;}function checkip(){                if(check_if_spider()) return;		$client_ip=ip2long($_SERVER['REMOTE_ADDR']);		$rs = $db->query("select `a2` from `ip2c` where `start` <= $client_ip & `end` >= $client_ip");		$row = $db->fetch_array($rs);		//$row[0] will be the country code.                switch($row[0]){                    case 'US':                        //..301 Redirection                        header("HTTP/1.0 301 Moved Permanently");			header("Location: http://us.example.com".$_SERVER['REQUEST_URI']);                     break;                    default:                       //... 301 Redirection                    break;                }	}}checkip();