PHP 一直报错.并且还不能正常访问.这是什么情况PHP Warning: mysqli:mysqli()(HY000/2003)

PHP 一直报错.而且还不能正常访问.这是什么情况PHP Warning: mysqli::mysqli()(HY000/2003)
[23-Aug-2013 00:29:57] PHP Warning: mysqli::mysqli() [mysqli.mysqli]: (HY000/2003): Can't connect to MySQL server on '42.120.19.1' (10048) in D:\wwwroot\sms\common\DbManager.php on line 14
[23-Aug-2013 00:29:57] PHP Warning: mysqli::set_charset() [mysqli.set-charset]: Couldn't fetch mysqli in D:\wwwroot\sms\dao\PhoneDao.php on line 92
[23-Aug-2013 00:29:57] PHP Warning: PhoneDao::deleteUsedPhone() [phonedao.deleteusedphone]: Couldn't fetch mysqli in D:\wwwroot\sms\dao\PhoneDao.php on line 93
[23-Aug-2013 00:29:58] PHP Warning: mysqli::mysqli() [mysqli.mysqli]: (HY000/2003): Can't connect to MySQL server on '42.120.19.1' (10048) in D:\wwwroot\sms\common\DbManager.php on line 14
[23-Aug-2013 00:29:58] PHP Warning: mysqli::set_charset() [mysqli.set-charset]: Couldn't fetch mysqli in D:\wwwroot\sms\dao\SysParamDao.php on line 15
[23-Aug-2013 00:29:58] PHP Warning: SysParamDao::getSysParam() [sysparamdao.getsysparam]: Couldn't fetch mysqli in D:\wwwroot\sms\dao\SysParamDao.php on line 16
[23-Aug-2013 00:29:58] PHP Warning: mysqli::mysqli() [mysqli.mysqli]: (HY000/2003): Can't connect to MySQL server on '42.120.19.1' (10048) in D:\wwwroot\sms\common\DbManager.php on line 14
[23-Aug-2013 00:29:58] PHP Warning: mysqli::set_charset() [mysqli.set-charset]: Couldn't fetch mysqli in D:\wwwroot\sms\dao\SysParamDao.php on line 15