centos下 mysql 无法启动

[root@localhost ~]# service mysqld start
Another MySQL daemon already running with the same unix socket.
正在启动 mysqld： [失败]

尝试重启，出现如下错误

[root@localhost ~]# /etc/init.d/mysqld status
mysqld 已停

可以执行该命令修复

mv /var/lib/mysql/mysql.sock /var/lib/mysql/mysql.sock.bak

参考：http://bbs.csdn.net/topics/390662731?page=1#post-396281623