How to move mariadb data directory out from /var

 This is a good reference:

https://www.tecmint.com/change-default-mysql-mariadb-data-directory-in-linux/

[root@database-rhel84 lib]# cd /data

[root@database-rhel84 data]# df -k

Filesystem                             1K-blocks    Used Available Use% Mounted on

devtmpfs                                 8075472       0   8075472   0% /dev

tmpfs                                    8105800       0   8105800   0% /dev/shm

tmpfs                                    8105800    9492   8096308   1% /run

tmpfs                                    8105800       0   8105800   0% /sys/fs/cgroup

/dev/mapper/rhel_database--rhel84-root  31441920 5157720  26284200  17% /

/dev/mapper/rhel_database--rhel84-data 104806400  763756 104042644   1% /data

/dev/sda2                                1038336  242324    796012  24% /boot

/dev/sr0                                 9892300 9892300         0 100% /cdrom

/dev/mapper/rhel_database--rhel84-home  11020288  123784  10896504   2% /home

/dev/sda1                                 613184    5892    607292   1% /boot/efi

tmpfs                                    1621160    1180   1619980   1% /run/user/42

tmpfs                                    1621160       0   1621160   0% /run/user/0

[root@database-rhel84 data]# mkdir mysql

[root@database-rhel84 data]# chown mysql:mysql mysql

[root@database-rhel84 data]# ls -l

total 0

drwxr-xr-x. 2 mysql mysql 6 Nov 12 22:37 mysql

[root@database-rhel84 data]# ls -l /var/lib/mssql

ls: cannot access '/var/lib/mssql': No such file or directory

[root@database-rhel84 data]# ls -l /var/lib/mysql

total 110628

-rw-rw----. 1 mysql mysql    24576 Nov 12 20:56 aria_log.00000001

-rw-rw----. 1 mysql mysql       52 Nov 12 20:56 aria_log_control

-rw-rw----. 1 mysql mysql      972 Nov 12 20:56 ib_buffer_pool

-rw-rw----. 1 mysql mysql 12582912 Nov 12 20:56 ibdata1

-rw-rw----. 1 mysql mysql 50331648 Nov 12 20:56 ib_logfile0

-rw-rw----. 1 mysql mysql 50331648 Nov 12 20:56 ib_logfile1

drwx------. 2 mysql mysql     4096 Nov 12 20:56 mysql

drwx------. 2 mysql mysql       20 Nov 12 20:56 performance_schema

drwx------. 2 mysql mysql       20 Nov 12 20:56 test

[root@database-rhel84 data]# date

Fri Nov 12 22:38:01 +08 2021

[root@database-rhel84 data]# systemctl stop mariadb

[root@database-rhel84 data]#  systemctl is-active mariadb

inactive

[root@database-rhel84 data]# service mysqld stop

Redirecting to /bin/systemctl stop mysqld.service

Failed to stop mysqld.service: Unit mysqld.service not loaded.

[root@database-rhel84 data]# cp -R -p /var/lib/mysql/* /data/mysql

[root@database-rhel84 data]# pwd

/data

[root@database-rhel84 data]# mv /var/lib/mysql /var/lib/mysql.old

[root@database-rhel84 data]# vi /etc/my.cnf

[root@database-rhel84 data]# cd /etc/my.cnf.d/

[root@database-rhel84 my.cnf.d]# ls -l

total 16

-rw-r--r--. 1 root root  295 Nov  6 03:03 client.cnf

-rw-r--r--. 1 root root  763 Nov  6 03:03 enable_encryption.preset

-rw-r--r--. 1 root root  232 Nov  6 03:03 mysql-clients.cnf

-rw-r--r--. 1 root root 1080 Nov  6 03:03 server.cnf

[root@database-rhel84 my.cnf.d]# vi server.cnf

[root@database-rhel84 my.cnf.d]# cp -p server.cnf server.cnf.orig

[root@database-rhel84 my.cnf.d]# vi server.cnf

[root@database-rhel84 my.cnf.d]# ls -l /data

total 0

drwxr-xr-x. 5 mysql mysql 181 Nov 12 22:40 mysql

[root@database-rhel84 my.cnf.d]# mvdatadir=/mnt/mysql-data

[root@database-rhel84 my.cnf.d]# socket=/mnt/mysql-data/mysql.sock ^C

[root@database-rhel84 my.cnf.d]# mv /data/mysql/ /data/mysql-data

[root@database-rhel84 my.cnf.d]# ls -l

total 20

-rw-r--r--. 1 root root  295 Nov  6 03:03 client.cnf

-rw-r--r--. 1 root root  763 Nov  6 03:03 enable_encryption.preset

-rw-r--r--. 1 root root  232 Nov  6 03:03 mysql-clients.cnf

-rw-r--r--. 1 root root 1140 Nov 12 22:43 server.cnf

-rw-r--r--. 1 root root 1080 Nov  6 03:03 server.cnf.orig

[root@database-rhel84 my.cnf.d]# pwd

/etc/my.cnf.d

[root@database-rhel84 my.cnf.d]# ls -l /data

total 0

drwxr-xr-x. 5 mysql mysql 181 Nov 12 22:40 mysql-data

[root@database-rhel84 my.cnf.d]# ls -l

total 20

-rw-r--r--. 1 root root  295 Nov  6 03:03 client.cnf

-rw-r--r--. 1 root root  763 Nov  6 03:03 enable_encryption.preset

-rw-r--r--. 1 root root  232 Nov  6 03:03 mysql-clients.cnf

-rw-r--r--. 1 root root 1140 Nov 12 22:43 server.cnf

-rw-r--r--. 1 root root 1080 Nov  6 03:03 server.cnf.orig

[root@database-rhel84 my.cnf.d]# cp -p client.cnf client.cnf.orig

[root@database-rhel84 my.cnf.d]# vi client.cnf

[root@database-rhel84 my.cnf.d]#

[root@database-rhel84 my.cnf.d]#

[root@database-rhel84 my.cnf.d]# semanage fcontext -a -t mysqld_db_t "/mnt/mysql-data(/.*)?"

[root@database-rhel84 my.cnf.d]# restorecon -R /mnt/mysql-data

restorecon: lstat(/mnt/mysql-data) failed: No such file or directory

[root@database-rhel84 my.cnf.d]# semanage fcontext -a -t mysqld_db_t "/data/mysql-data(/.*)?"

[root@database-rhel84 my.cnf.d]# restorecon -R /data/mysql-data

[root@database-rhel84 my.cnf.d]# systemctl start mariadb

[root@database-rhel84 my.cnf.d]# systemctl is-active mariadb

active

[root@database-rhel84 my.cnf.d]# systemctl status  mariadb

● mariadb.service - MariaDB 10.4.22 database server

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

  Drop-In: /etc/systemd/system/mariadb.service.d

           └─migrated-from-my.cnf-settings.conf

   Active: active (running) since Fri 2021-11-12 22:46:51 +08; 18s ago

     Docs: man:mysqld(8)

           https://mariadb.com/kb/en/library/systemd/

  Process: 37931 ExecStartPost=/bin/sh -c systemctl unset-environment _WSREP_START_POSITION (code=exited, status=0/SUCCESS)

  Process: 37882 ExecStartPre=/bin/sh -c [ ! -e /usr/bin/galera_recovery ] && VAR= ||   VAR=`cd /usr/bin/..; /usr/bin/galera_recovery`; [ $? -eq 0 ]   && systemctl se>

  Process: 37880 ExecStartPre=/bin/sh -c systemctl unset-environment _WSREP_START_POSITION (code=exited, status=0/SUCCESS)

 Main PID: 37899 (mysqld)

   Status: "Taking your SQL requests now..."

    Tasks: 30 (limit: 100943)

   Memory: 73.6M

   CGroup: /system.slice/mariadb.service

           └─37899 /usr/sbin/mysqld

Nov 12 22:46:51 database-rhel84 mysqld[37899]: 2021-11-12 22:46:51 0 [Note] InnoDB: 10.4.22 started; log sequence number 60967; transaction id 20

Nov 12 22:46:51 database-rhel84 mysqld[37899]: 2021-11-12 22:46:51 0 [Note] InnoDB: Loading buffer pool(s) from /data/mysql-data/ib_buffer_pool

Nov 12 22:46:51 database-rhel84 mysqld[37899]: 2021-11-12 22:46:51 0 [Note] Plugin 'FEEDBACK' is disabled.

Nov 12 22:46:51 database-rhel84 mysqld[37899]: 2021-11-12 22:46:51 0 [Note] InnoDB: Buffer pool(s) load completed at 211112 22:46:51

Nov 12 22:46:51 database-rhel84 mysqld[37899]: 2021-11-12 22:46:51 0 [Note] Server socket created on IP: '::'.

Nov 12 22:46:51 database-rhel84 mysqld[37899]: 2021-11-12 22:46:51 0 [Note] Reading of all Master_info entries succeeded

Nov 12 22:46:51 database-rhel84 mysqld[37899]: 2021-11-12 22:46:51 0 [Note] Added new Master_info '' to hash table

Nov 12 22:46:51 database-rhel84 mysqld[37899]: 2021-11-12 22:46:51 0 [Note] /usr/sbin/mysqld: ready for connections.

Nov 12 22:46:51 database-rhel84 mysqld[37899]: Version: '10.4.22-MariaDB'  socket: '/data/mysql-data/mysql.sock'  port: 3306  MariaDB Server

Nov 12 22:46:51 database-rhel84 systemd[1]: Started MariaDB 10.4.22 database server.

[root@database-rhel84 my.cnf.d]#  mysql -u root -p -e "SELECT @@datadir;"

Enter password:

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

[root@database-rhel84 my.cnf.d]# systemctl stop mariadb

[root@database-rhel84 my.cnf.d]# vi client.cnf

[root@database-rhel84 my.cnf.d]# vi server.cnf

[root@database-rhel84 my.cnf.d]# systemctl start mariadb

[root@database-rhel84 my.cnf.d]# systemctl status  mariadb

● mariadb.service - MariaDB 10.4.22 database server

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

  Drop-In: /etc/systemd/system/mariadb.service.d

           └─migrated-from-my.cnf-settings.conf

   Active: active (running) since Fri 2021-11-12 22:48:08 +08; 3s ago

     Docs: man:mysqld(8)

           https://mariadb.com/kb/en/library/systemd/

  Process: 38034 ExecStartPost=/bin/sh -c systemctl unset-environment _WSREP_START_POSITION (code=exited, status=0/SUCCESS)

  Process: 37987 ExecStartPre=/bin/sh -c [ ! -e /usr/bin/galera_recovery ] && VAR= ||   VAR=`cd /usr/bin/..; /usr/bin/galera_recovery`; [ $? -eq 0 ]   && systemctl se>

  Process: 37985 ExecStartPre=/bin/sh -c systemctl unset-environment _WSREP_START_POSITION (code=exited, status=0/SUCCESS)

 Main PID: 38003 (mysqld)

   Status: "Taking your SQL requests now..."

    Tasks: 30 (limit: 100943)

   Memory: 71.7M

   CGroup: /system.slice/mariadb.service

           └─38003 /usr/sbin/mysqld

Nov 12 22:48:07 database-rhel84 mysqld[38003]: 2021-11-12 22:48:07 0 [Note] InnoDB: 10.4.22 started; log sequence number 60976; transaction id 20

Nov 12 22:48:07 database-rhel84 mysqld[38003]: 2021-11-12 22:48:07 0 [Note] InnoDB: Loading buffer pool(s) from /data/mysql-data/ib_buffer_pool

Nov 12 22:48:07 database-rhel84 mysqld[38003]: 2021-11-12 22:48:07 0 [Note] InnoDB: Buffer pool(s) load completed at 211112 22:48:07

Nov 12 22:48:07 database-rhel84 mysqld[38003]: 2021-11-12 22:48:07 0 [Note] Plugin 'FEEDBACK' is disabled.

Nov 12 22:48:07 database-rhel84 mysqld[38003]: 2021-11-12 22:48:07 0 [Note] Server socket created on IP: '::'.

Nov 12 22:48:07 database-rhel84 mysqld[38003]: 2021-11-12 22:48:07 0 [Note] Reading of all Master_info entries succeeded

[root@database-rhel84 my.cnf.d]#  mysql -u root -p -e "SELECT @@datadir;"

Enter password:

+-------------------+

| @@datadir         |

+-------------------+

| /data/mysql-data/ |