Can't connect to local MySQL server through socket

Mysql连接提示：

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock'

如下：

[root@cacti01 ~]# mysql
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)
[root@cacti01 ~]# mysql -h localhost -p -u root
Enter password:
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)

而那个文件是压根不存在的：

[root@cacti01 ~]# more /var/lib/mysql/mysql.sock
/var/lib/mysql/mysql.sock: No such device or address

经查为mysqld服务没启动，启动后登录正常。

[root@cacti01 ~]# service mysqld start
Starting mysqld:                                           [  OK  ]
[root@cacti01 ~]# mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.1.61 Source distribution

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mysql>

状态查询：

[root@cacti01 ~]# service mysqld status
mysqld (pid  16211) is running...

正常后上面的那个文件还是不存在的，所以跟那个没有关系。