SQLSTATE[HY000] [2002] Connection refused

FILE: /mnt/wwwroot/newjiagu/ThinkPHP/Library/Think/Db/Driver.class.php 　LINE: 109

#0 /mnt/wwwroot/newjiagu/ThinkPHP/Library/Think/Db/Driver.class.php(109): E('SQLSTATE[HY000]...')
#1 /mnt/wwwroot/newjiagu/ThinkPHP/Library/Think/Db/Driver.class.php(1075): Think\Db\Driver->connect()
#2 /mnt/wwwroot/newjiagu/ThinkPHP/Library/Think/Db/Driver/Mysql.class.php(47): Think\Db\Driver->initConnect(true)
#3 /mnt/wwwroot/newjiagu/ThinkPHP/Library/Think/Model.class.php(134): Think\Db\Driver\Mysql->getFields('tc_denied_ip')
#4 /mnt/wwwroot/newjiagu/ThinkPHP/Library/Think/Model.class.php(122): Think\Model->flush()
#5 /mnt/wwwroot/newjiagu/ThinkPHP/Library/Think/Model.class.php(1454): Think\Model->_checkTableInfo()
#6 /mnt/wwwroot/newjiagu/ThinkPHP/Library/Think/Model.class.php(97): Think\Model->db(0, '', true)
#7 /mnt/wwwroot/newjiagu/ThinkPHP/Common/functions.php(621): Think\Model->__construct('denied_ip', '', '')
#8 /mnt/wwwroot/newjiagu/Application/Home/Controller/BaseController.class.php(28): M('denied_ip')
#9 /mnt/wwwroot/newjiagu/ThinkPHP/Common/functions.php(681): Home\Controller\BaseController->__construct()
#10 /mnt/wwwroot/newjiagu/ThinkPHP/Library/Think/App.class.php(89): controller('Index', '')
#11 /mnt/wwwroot/newjiagu/ThinkPHP/Library/Think/App.class.php(204): Think\App::exec()
#12 /mnt/wwwroot/newjiagu/ThinkPHP/Library/Think/Think.class.php(120): Think\App::run()
#13 /mnt/wwwroot/newjiagu/ThinkPHP/ThinkPHP.php(97): Think\Think::start()
#14 /mnt/wwwroot/newjiagu/www/index.php(34): require('/mnt/wwwroot/ne...')
#15 {main}