1,关闭mysql服务:
service mysqld stop
2,创建新建的目录
mkdir -p data
3,把以前的目录转移到新的数据目录
mv /var/lib/mysql/ /data/
4,编辑my.cnf
vi /etc/my.cnf
修改其中的datadir和socket到新的路径
[mysqld]
datadir=/data/mysql
socket=/data/mysql/mysql.sock
5、修改MySQL启动脚本/etc/init.d/mysql
最后,需要修改MySQL启动脚本/etc/init.d/mysql,把其中datadir=/var/lib/mysql一行中,等号右边的路径改成你现在的实际存放路径:/data/mysql
本以为修改完启动mysql服务之后就没问题了。
service mysqld start
/etc/init.d/mysql start
但是尽管启动服务没有问题,但是通过mysql客户端连接的时候却报错:
[root@test data]# mysql -u root -p
Enter password:
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)
提示说无法通过socket文件/var/lib/mysql/mysql.sock连接到mysql服务器,也就是说对于mysql程序来说,尽管我把socket文件从/var/lib/mysql/mysql.sock转移到了/data/mysql/mysql.sock我在my.cnf里指定了mysqld知道了,但是对于mysql还是会从默认的安装目录/var/lib/mysql/里找这个mysql.sock文件,找不着,就不知道从哪里启动了。
解决办法一:
ln –s /data/mysql/mysql.sock /var/lib/mysql/
做完软连接,重启mysql服务,再次通过mysql程序连接,没有问题,可以连上了。
[root@test lib]# mysql -u root -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.0.77 Source distribution
Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
mysql>
那说明就是这里的问题了。
方法二:其实不做软链接也是可以的,只需要在/etc/my.cnf里添加[mysql]字段指定socket的位置到我们转移后的位置即可
[mysql]
socket=/data/mysql/mysql.sock
方法三:修改权限
chown -R mysql:mysql /data/mysql/
chmod 660 /data/mysql/test/*
以上几种方法经过试验还是切实可行的,希望对大家更改目录有帮助。

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