阿里云mysql 数据切换到新的磁盘下

原目录：/usr/local/mysql/data/
新目录：/data/mysqldata/

1，停止mysq服务
service mysqld stop

2，复制或移动数据库到新目录
cp -R /usr/local/mysql/data/* /data/mysqldata/

或者移动

mv /usr/local/mysql/data/* /data/mysqldata/

3，赋于mysql目录权限
chown -R mysql:mysql /data/mysqldata/

4,修改mysql配置文件
vi /etc/my.cnf
#datadir = /usr/local/mysql/data/
datadir = /data/mysqldata/

5，启动mysqld服务
service mysqld start

用ps -ef |grep mysql 命令查看mysql进程启动的所有配置信息

root      4085     1  0 00:59 pts/0    00:00:00 /bin/sh /a/apps/mysql-5.1.73/bin/mysqld_safe --datadir=/data/mysqldata/ --pid-file=/data/mysqldata/ iZ258h0tep1Z.pid

mysql     4258  4085  0 00:59 pts/0    00:00:01 /a/apps/mysql-5.1.73/libexec/mysqld --basedir=/a/apps/mysql-5.1.73 --datadir=/data/mysqldata/ --user=mysql --log-error=/a/apps/mysql-5.1.73/log/mysqld.log --open-files-limit=4096 --pid-file=/data/mysqldata/iZ258h0tep1Z.pid --socket=/tmp/mysql.sock

--datadir已经是新目录了

如果出现以下类似错误：chown -R mysql:mysql /data/mysqldata/ 修改权限即可

MySQL manager or server PID file could not be found!       [FAILED]

Starting MySQL.Manager of pid-file quit without updating fi

查看数据库的的日志文件的时候出现

tail -n 30 mysqld.log 

150706  0:55:12 [ERROR] /a/apps/mysql-5.1.73/libexec/mysqld: Can't create/write to file '/mysql/data/iZ258h0tep1Z.pid' (Errcode: 13)

150706  0:55:12 [ERROR] Can't start server: can't create PID file: Permission denied

150706 00:55:12 mysqld_safe mysqld from pid file /dingguidata/iZ258h0tep1Z.pid ended