场景：vmvare虚拟机、centos7、mysql5.7
解决：
mv /var/lib/mysql/mysql.sock /var/lib/mysql/mysql.sock.bak
参考：
http://stackoverflow.com/questions/20407292/centos-another-mysql-daemon-already-running-with-the-same-unix-socket
Mysql启动时提示：Another MySQL daemon already running with the same unix socket.
原文：http://www.cnblogs.com/grey-wolf/p/6605360.html