user-agent:Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/47.0.2526.106 Safari/537.36
user-agent:Mozilla/5.0 (iPhone; CPU iPhone OS 8_0 like Mac OS X) AppleWebKit/600.1.3 (KHTML, like Gecko) Version/8.0 Mobile/12A4345d Safari/600.1.4
user-agent:Mozilla/5.0 (Linux; Android 4.3; Nexus 10 Build/JSS15Q) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/42.0.2307.2 Safari/537.36
server{
listen 80;
server_name test.9h.com;
if ( $http_user_agent ~ "(MIDP)|(WAP)|(UP.Browser)|(Smartphone)|(Obigo)|(Mobile)|(AU.Browser)|(wxd.Mms)|(WxdB.Browser)|(CLDC)|(UP.Link)|(KM.Browser)|(UCWEB)|(SEMC\-Browser)|(Mini)|(Symbian)|(Palm)|(Nokia)|(Panasonic)|(MOT\-)|(SonyEricsson)|(NEC\-)|(Alcatel)|(Ericsson)|(BENQ)|(BenQ)|(Amoisonic)|(Amoi\-)|(Capitel)|(PHILIPS)|(SAMSUNG)|(Lenovo)|(Mitsu)|(Motorola)|(SHARP)|(WAPPER)|(LG\-)|(LG/)|(EG900)|(CECT)|(Compal)|(kejian)|(Bird)|(BIRD)|(G900/V1.0)|(Arima)|(CTL)|(TDG)|(Daxian)|(DAXIAN)|(DBTEL)|(Eastcom)|(EASTCOM)|(PANTECH)|(Dopod)|(Haier)|(HAIER)|(KONKA)|(KEJIAN)|(LENOVO)|(Soutec)|(SOUTEC)|(SAGEM)|(SEC\-)|(SED\-)|(EMOL\-)|(INNO55)|(ZTE)|(iPhone)|(Android)|(Windows CE)|(Wget)|(Java)|(curl)|(Opera)" )
{
rewrite ^.+ http://www.baidu.com;
}
root /var/www/html/test/;
}
ua实现类似 www.taobao.com 在手机上打开自动转变为 m.taobao.com 的域名转换
原文：http://www.cnblogs.com/tq1226112215/p/5276574.html