mysql启动错误：server PID file could not be found!

[root@localhost ~]#service mysqld stop MySQL manager or server PID file could not be found!

首先查看一下进程：
#ps –aux|grep mysql
root 15555 0.0 0.0 197956 2308 pts/2 ? S+ 02:49 0:00 mysql -u root –p
root 23222 0.0 0.0 103300 844 pts/3 ? S+ 03:21 0:00 grep mysql
如果看到上面的信息，说明mysql的进程卡死了，这时就要把mysql的进程杀死;

#kill 15555
#kill 23222

然后重启mysql服务即可:
service mysql start