$ _SERVER ['SERVER_ADDR']不等于真实服务器IP地址

I am working on a dedicated server, yet the IP address returns by $_SERVER['SERVER_ADDR'] is different from the real IP address of the server.

Would you happen to know how this is possible? Thanks

Try using,

$_SERVER['HTTP_X_FORWARDED_FOR']

reference HTTP_X_FORWARDED_FOR

you can use,

gethostbyname($_SERVER['SERVER_NAME'])

or

getHostByName(php_uname('n'))