[root@master mysql]# mysql -uroot -pjsb ERROR 2002 (HY000): Can't connect to local MySQL server thro

ERROR 2002 (HY000): Cant connect to local MySQL server through socket /var/lib/mysql/mysql.sock (2)

#查看mysql实例的状态
[root@SZDB mysqldata]# netstat -ntlp  | grep 3306
tcp        0      0 :::3306                     :::*                        LISTEN      13001/mysqld
#查看my.cnf关于socket的配置
[root@SZDB mysqldata]# more /etc/my.cnf |grep sock
socket = /tmp/mysql.sock
#由上可知my.cnf中定义的为/tmp目录下，而错误提示为/data/mysqldata/目录下
#也就是说mysqld已经声称了正确的sock文件，但客户端连接还是从初始目录去找sock文件
#下面查看后台日志，有个ERROR，是关于满查询日志的，是由于目录不存在而产生的错误，与当前故障无关
[root@SZDB mysqldata]# more SZDB.err
             ............
2014-10-11 13:17:21 13001 [Note] InnoDB: 5.6.12 started; log sequence number 1625997
/app/soft/mysql/bin/mysqld: File /log/mysql_logs/slowquery.log not found (Errcode: 2 - No such file or directory)
2014-10-11 13:17:21 13001 [ERROR] Could not use /log/mysql_logs/slowquery.log for logging (error 2). Turning logging off for the who
le duration of the MySQL server process. To turn it on again: fix the cause, shutdown the MySQL server and restart it.
2014-10-11 13:17:21 13001 [Note] Server hostname (bind-address): *; port: 3306
2014-10-11 13:17:21 13001 [Note] IPv6 is available.
2014-10-11 13:17:21 13001 [Note]   - :: resolves to ::;
2014-10-11 13:17:21 13001 [Note] Server socket created on IP: ::.
2014-10-11 13:17:21 13001 [Note] Event Scheduler: Loaded 0 events
2014-10-11 13:17:21 13001 [Note] /app/soft/mysql/bin/mysqld: ready for connections.
Version: 5.6.12-log  socket: /tmp/mysql.sock  port: 3306  Source distribution

#先停止mysql服务器
[root@SZDB mysqldata]# service mysqld stop
Shutting down MySQL.[  OK  ]
#修改my.cnf，如下
[root@SZDB mysqldata]# vi /etc/my.cnf
[mysql]
no-auto-rehash
socket = /tmp/mysql.sock  #添加该行
#重启mysql服务器
[root@SZDB mysqldata]# service mysqld start
Starting MySQL..[  OK  ]
#再次连接正常
[root@SZDB mysqldata]# mysql -uroot -p
Enter password:
mysql show variables like version;
+---------------+------------+
| Variable_name | Value      |
+---------------+------------+
| version       | 5.6.12-log |
+---------------+------------+

解决方法

[root@SZDB mysqldata]# ln -s /tmp/mysql.sock /data/mysqldata/mysql.sock ln: creating symbolic link `/data/mysqldata/mysql.sock to `/tmp/mysql.sock: File exists
[root@SZDB mysqldata]# rm mysql.sock    #上面提示文件存在，所以删除之前的mysql.sock文件
[root@SZDB mysqldata]# ln -s /tmp/mysql.sock /data/mysqldata/mysql.sock
[root@SZDB mysqldata]# ls -hltr mysql.sock
lrwxrwxrwx 1 root root 15 Oct 11 14:00 mysql.sock - /tmp/mysql.sock
[root@SZDB mysqldata]# mysql -uroot -p
Enter password:
mysql show variables like socket;
+---------------+-----------------+
| Variable_name | Value           |
+---------------+-----------------+
| socket        | /tmp/mysql.sock |
+---------------+-----------------+