mariadb-2-在centos中修改mariadb資料的儲存路徑

(1)mariadb的預設儲存目錄
Mariadb 預設的資料儲存目錄為 /var/lib/mysql。
MariaDB [(none)]> create database mytest;
MariaDB [mytest]> create table student(name varchar(10),age int);
MariaDB [mytest]> insert into student(name,age) values (‘lucy’,11);

新建的資料庫，在目錄中以資料夾的形式存在。

#mkdir /mydata建立需要遷移到的新目錄
#chmod 777 /mydata加上讀寫許可權
#systemctl stop mariadb.service停止Mariadb服務

(2)修改配置檔案/etc/my.cnf
修改datadir=/var/lib/mysql
修改log-error=/var/log/mariadb/mariadb.log

# include *.cnf from the config directory
#
!includedir /etc/my.cnf.d
[mysqld]
init_connect='SET collation_connection = utf8_unicode_ci'
init_connect='SET NAMES utf8'
character-set-server=utf8
collation-server=utf8_unicode_ci
skip-character-set-client-handshake

#datadir=/var/lib/mysql
datadir=/mydata/mysql
socket=/var/lib/mysql/mysql.sock
symbolic-links=0
# Settings user and group are ignored when systemd is used.
# If you need to run mysqld under a different user or group,
# customize your systemd unit file for mariadb according to the
# instructions in http://fedoraproject.org/wiki/Systemd

[mysqld_safe]
#log-error=/var/log/mariadb/mariadb.log
log-error=/mydata/log/mariadb/mariadb.log
pid-file=/var/run/mariadb/mariadb.pid

注意：不要修改socket和pid-file路徑，否者容易出錯。
(3)複製檔案
將/var/lib/mysql下面的檔案複製到/mydata/mysql，
將/var/log/mariadb/複製到/mydata/log/mariadb
#mkdir /mydata
#cp -a /var/lib/mysql/ /mydata/
#mkdir /mydata/log/
#cp -a /var/log/mariadb/ /data/log/
#chown -R mysql:mysql /mydata/

(4)注意：如果開啟了SELinux和防火牆，需要關閉SELinux和firewall
或者設定/data/、/data/log/的security context，開啟3306埠

修改security context（如果開啟了selinux，需要，否則跳過）
檢視/var/lib/mysql 的security context
#ls -Z /var/lib/mysql/
-rw-rw----. mysql mysql system_u:object_r:mysqld_db_t:s0 aria_log.00000001
-rw-rw----. mysql mysql system_u:object_r:mysqld_db_t:s0 aria_log_control
-rw-rw----. mysql mysql system_u:object_r:mysqld_db_t:s0 ibdata1
-rw-rw----. mysql mysql system_u:object_r:mysqld_db_t:s0 ib_logfile0
-rw-rw----. mysql mysql system_u:object_r:mysqld_db_t:s0 ib_logfile1
drwx------. mysql mysql system_u:object_r:mysqld_db_t:s0 mysql
drwx------. mysql mysql system_u:object_r:mysqld_db_t:s0 performance_schema
修改、恢復/data/mysql，/data/log的security context
#semanage fcontext -a -t mysqld_db_t “/data/mysql(/.)?"
#restorecon -R -v /data/mysql
#semanage fcontext -a -t mysqld_db_t "/data/log(/.)?”
#restorecon -R -v /data/log
(5)重新啟動 Mariadb 服務
#systemctl start mariadb.service

可以看到新的資料庫已經出現在遷移後的目錄裡了。