MySQL（Mariadb）启动失败

问题

修改/etc/my.conf文件中的数据保存目录后，mariadb启动失败。

排查

使用systemctl status mariadb.service查看原因

[root@linux-4-193 mysql]# systemctl status mariadb.service

● mariadb.service - MariaDB database server

   Loaded: loaded (/usr/lib/systemd/system/mariadb.service; disabled; vendor preset: disabled)

   Active: failed (Result: exit-code) since 三 2022-01-12 21:02:39 EST; 2s ago

  Process: 11377 ExecStartPost=/usr/libexec/mariadb-wait-ready $MAINPID (code=exited, status=1/FAILURE)

  Process: 11375 ExecStart=/usr/bin/mysqld_safe --basedir=/usr (code=exited, status=0/SUCCESS)

  Process: 11247 ExecStartPre=/usr/libexec/mariadb-prepare-db-dir %n (code=exited, status=0/SUCCESS)

 Main PID: 11375 (code=exited, status=0/SUCCESS)

1月 12 21:02:38 linux-4-193 mariadb-prepare-db-dir[11247]: You can find additional information about the MySQL part at:

1月 12 21:02:38 linux-4-193 mariadb-prepare-db-dir[11247]: http://dev.mysql.com

1月 12 21:02:38 linux-4-193 mariadb-prepare-db-dir[11247]: Consider joining MariaDB's strong and vibrant community:

1月 12 21:02:38 linux-4-193 mariadb-prepare-db-dir[11247]: https://mariadb.org/get-involved/

1月 12 21:02:38 linux-4-193 mysqld_safe[11375]: 220112 21:02:38 mysqld_safe Logging to '/var/log/mariadb/mariadb.log'.

1月 12 21:02:38 linux-4-193 mysqld_safe[11375]: 220112 21:02:38 mysqld_safe Starting mysqld daemon with databases from /data/mysql

1月 12 21:02:39 linux-4-193 systemd[1]: mariadb.service: control process exited, code=exited status=1

1月 12 21:02:39 linux-4-193 systemd[1]: Failed to start MariaDB database server.

1月 12 21:02:39 linux-4-193 systemd[1]: Unit mariadb.service entered failed state.

1月 12 21:02:39 linux-4-193 systemd[1]: mariadb.service failed.

[root@linux-4-193 mysql]# ll

根据提示查看mariadb启动日志

[root@linux-4-193 mysql]# cat /var/log/mariadb/mariadb.log

220112 01:08:28 mysqld_safe Starting mysqld daemon with databases from /data/mysql

220112  1:08:28 [Note] /usr/libexec/mysqld (mysqld 5.5.68-MariaDB) starting as process 22271 ...

220112  1:08:28 [Warning] Can't create test file /data/mysql/linux-4-193.lower-test

220112  1:08:28 InnoDB: The InnoDB memory heap is disabled

220112  1:08:28 InnoDB: Mutexes and rw_locks use GCC atomic builtins

220112  1:08:28 InnoDB: Compressed tables use zlib 1.2.7

220112  1:08:28 InnoDB: Using Linux native AIO

220112  1:08:28 InnoDB: Initializing buffer pool, size = 128.0M

220112  1:08:28 InnoDB: Completed initialization of buffer pool

220112  1:08:28  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: 'create'.

InnoDB: Cannot continue operation.

220112 01:08:28 mysqld_safe mysqld from pid file /var/run/mariadb/mariadb.pid ended

The error means mysqld does not have the access rights to

可以看到是没有目录的处理权限。

解决

执行 chown mysql:mysql data 赋予mysql用户数据目录的权限即可。