Linux下更改MySQL数据库存储路径（实践常用）

第1步：使用第三方软件SSH或xshell成功登录到centos系统。

第2步:home目录下建立data目录,data目录下建立mysql目录

第3步：首先停止掉mysql服务，在终端中执行"/etc/init.d/mysql stop" 或者执行"service mysqld stop"并回车确定。

第4步： 把/var/lib/mysql整个目录移到/home/data/下

第5步：修改mysql配置文件，执行“vim /etc/my.cnf”命令并确定。

第6步：修改mysql配置文件，修改MySQL启动脚本/etc/init.d/mysqld。

执行"vim /etc/init.d/mysqld "（如果没有此文件，就不需要修改）

第7步：重新启动MySQL服务
 service mysqld restart  或者/etc/init.d/mysqld start

 

可能遇到的问题：

The server quit without updating PID file.

问题解析：

可能是没有将原数据库文件拷贝到新的目录下面，或者没有将新建的目录授权给mysql用户（chown -R mysql:mysql /home/data/mysql）

ps.补充，查看用户组 cat /etc/group

chown -R mysql:mysql /home/data/mysql

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)

https://www.linuxidc.com/Linux/2013-03/81331.htm

问题描述：

[root@localhost ~]# mysql -uroot -p

ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)

修改/etc/my.cnf:
[mysqld]
datadir=/usr/local/mysql/data
#socket=/var/lib/mysql/mysql.sock

socket=/home/data/mysql/mysql.sock

[mysql.server]
user=mysql
basedir=/usr/local/mysql

If there is not currently a section called [client], add one at the bottom of the file and copy the socket= line under the [mysqld] section such as:

[client]
socket=/home/data/mysql/mysql.sock

保持退出

然后重启MySQL，执行命令：systemctl restart mysqld.service

 

mysql数据库报错：InnoDB: Operating system error number 13 in a file operation

环境：centos6.5 x86_64

启动mysql发现日志报错(日志路径可以查看/etc/my.cnf的配置，例如 /var/log/mysqld.log)

160722 10:34:08 [Note] Found 42570716 of 42570696 rows when repairing './yunva@002dlog/room_msg'

160810  0:54:00 [ERROR] /usr/libexec/mysqld: Sort aborted
160810 10:41:55 [ERROR] /usr/libexec/mysqld: Sort aborted
160810 16:41:43 [ERROR] /usr/libexec/mysqld: Sort aborted
160823 11:34:45 mysqld_safe Starting mysqld daemon with databases from /home/data
160823 11:34:46 [Warning] Can't create test file /home/data/plugin.lower-test
160823 11:34:46 [Warning] Can't create test file /home/data/plugin.lower-test
160823 11:34:46 [Warning] option 'innodb-additional-mem-pool-size': signed value 200 adjusted to 524288
160823 11:34:46  InnoDB: Initializing buffer pool, size = 128.0M
160823 11:34:46  InnoDB: Completed initialization of buffer pool
160823 11:34:46  InnoDB: Operating system error number 13 in a file operation.
InnoDB: The error means mysqld does not have the access rights to
InnoDB: the directory.
InnoDB: File name ./ibdata1
InnoDB: File operation call: 'open'.
InnoDB: Cannot continue operation.
160823 11:34:46 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended
160823 11:45:30 mysqld_safe Starting mysqld daemon with databases from /home/data
160823 11:45:30 [Warning] Can't create test file /home/data/plugin.lower-test
160823 11:45:30 [Warning] Can't create test file /home/data/plugin.lower-test
160823 11:45:30 [Warning] option 'innodb-additional-mem-pool-size': signed value 200 adjusted to 524288
160823 11:45:30  InnoDB: Initializing buffer pool, size = 128.0M
160823 11:45:30  InnoDB: Completed initialization of buffer pool
160823 11:45:30  InnoDB: Operating system error number 13 in a file operation.
InnoDB: The error means mysqld does not have the access rights to
InnoDB: the directory.
InnoDB: File name ./ibdata1
InnoDB: File operation call: 'open'.

InnoDB: Cannot continue operation.

发现系统启动只有几十分钟，说明服务器刚被人重启过，mysql服务无法启动

百度了下可能是selinux引起的，getenforce 发现问enforcing

setenforce 0

并且修改配置vim /etc/sysconfig/selinux

SELINUX=disabled

问题解决

转载原文：https://blog.csdn.net/weixin_34368949/article/details/94196444

mysql重启失败报错ibdata1 Can't determine file permissions

[ERROR] InnoDB: os_file_get_status() failed on './ibdata1'. Can't determine file permissions

mysql重启报错以上.

版本：mysql5.7+centos7.0

解决步骤：

    1、查看配置文件内容指定的pid-file

cat /etc/my.cnf
pid-file=/var/run/mysqld/mysqld.pid

    so，查看该目录是否存在。如没有，则创建，并修改属主属组。

ll /var/run/mysqld/
#不存在
mkdir -p /var/run/mysqld/
chown -R mysql:mysql /var/run/mysqld

    试着重启：

service mysqld restart

    如果还报错，则进入下一步。

    2、关闭selinux.并重启。

setenforce 0

    service mysqld restart

或者

   systemctl restart mysqld.service

转载原文链接：https://blog.csdn.net/agonisq/article/details/79817397