MySQL的备份还原(xtrabackup)

MySQL的备份还原(xtrabackup)

xtrabackup简介

xtrabackup是percona提供的MySQL数据库的备份工具，是唯一开源的能对innodb和xtradb数据库进行热备的工具

xtrabackup的特点

1.备份还原过程快、可靠
2.备份过程不会打断正在执行的事务
3.能够基于压缩等功能介于磁盘空间和流量
4.自动实现备份检验
5.开源免费

xtrabackup备份过程

xtrabackup安装

xtrabackup在centos的EPEL源中，可以在配置完EPEL源后使用yum安装

[[email protected] ~]# yum install -y percona-xtrabackup

也可以去官网下载最新版本的xtrabackup
https://www.percona.com/downloads/XtraBackup/LATEST

xtrabackup使用

xtrabackup [option] BACKUP-ROOT-DIR

xtrabackup完全，增量备份及还原

完全备份及还原

在完全备份之前需要创建一个备份的目录作为存放备份使用

[[email protected] ~]# mkdir /data/backup

数据库内存放的数据

[[email protected] ~]# mysql -e ‘SHOW DATABASES;‘
+--------------------+
| Database           |
+--------------------+
| hellodb            |
| information_schema |
| mysql              |
| performance_schema |
| test               |
+--------------------+

一、完全备份

[[email protected] ~]# mariabackup --backup --target-dir=/data/backup  --user=root --password=‘‘

二、对数据库破坏

[[email protected] ~]# rm -rf /data/mysql/*

三、恢复

3.1在恢复数据库前需要先将数据库内数据清理，然后停止mysql服务

[[email protected] ~]# rm -rf /data/mysql/*
[[email protected] ~]# service mysqld stop
Stopping mysqld (via systemctl):                           [  OK  ]

3.2对备份目录做整理

[[email protected] ~]# mariabackup --prepare --target-dir=/data/backup

3.3将整理好的备份数据还原至数据库

[[email protected] ~]# mariabackup --copy-back --target-dir=/data/backup

3.4此时还原回去的数据属性还有问题，需要将其修改

[[email protected] ~]# ll /data/mysql/
total 12320
-rw-r----- 1 root root    16384 May  6 21:28 aria_log.00000001
-rw-r----- 1 root root       52 May  6 21:28 aria_log_control
drwx------ 2 root root      272 May  6 21:28 hellodb
-rw-r----- 1 root root      942 May  6 21:28 ib_buffer_pool
-rw-r----- 1 root root 12582912 May  6 21:28 ibdata1
drwx------ 2 root root     4096 May  6 21:28 mysql
drwx------ 2 root root       20 May  6 21:28 performance_schema
drwx------ 2 root root       20 May  6 21:28 test
-rw-r----- 1 root root      527 May  6 21:28 xtrabackup_info

[[email protected] ~]# chown -R mysql.mysql /data/mysql/

四、启动服务测试

[[email protected] ~]# service mysqld start
Starting mysqld (via systemctl):                           [  OK  ]
[[email protected] ~]# mysql -e "SHOW DATABASES;SHOW TABLES FROM hellodb;"
+--------------------+
| Database           |
+--------------------+
| hellodb            |
| information_schema |
| mysql              |
| performance_schema |
| test               |
+--------------------+
+-------------------+
| Tables_in_hellodb |
+-------------------+
| classes           |
| coc               |
| courses           |
| scores            |
| students          |
| teachers          |
| toc               |
+-------------------+

完全备份+增量备份及还原

在备份之前先创建出完全备份的目录以及增量备份的目录

[[email protected] ~]# mkdir -pv /dataa/backup/{full,inc1,inc2}
mkdir: created directory ‘/data/backup’
mkdir: created directory ‘/data/backup/full’
mkdir: created directory ‘/data/backup/inc1’
mkdir: created directory ‘/data/backup/inc2’

数据库内所存放的数据

[[email protected] ~]# mysql -e ‘SHOW DATABASES;‘
+--------------------+
| Database           |
+--------------------+
| hellodb            |
| information_schema |
| mysql              |
| performance_schema |
| test               |
+--------------------+

一、对数据进行完全备份

[[email protected] ~]# mariabackup --backup --target-dir=/data/backup/full --user=root --password=‘‘

二、此时数据库内数据发生变化

[[email protected] ~]# mysql -e "INSERT hellodb.teachers VALUE(5,‘Li Xiaolong‘,30,‘M‘);"
[[email protected] ~]# mysql -e "SELECT * FROM hellodb.teachers WHERE tid>4;"
+-----+-------------+-----+--------+
| TID | Name        | Age | Gender |
+-----+-------------+-----+--------+
|   5 | Li Xiaolong |  30 | M      |
+-----+-------------+-----+--------+

三、对数据库进行增量备份

[[email protected] ~]# mariabackup --user=root --password=‘‘ --backup --incremental-basedir=/data/backup/full --target-dir=/data/backup/inc1

四、数据库内数据再次发生变化

[[email protected] ~]# mysql -e "INSERT hellodb.students(stuid,age,name) VALUE (26,35,‘Sun Wukong‘);"
[[email protected] ~]# mysql -e "SELECT * FROM hellodb.students WHERE stuid>25;"
+-------+------------+-----+--------+---------+-----------+
| StuID | Name       | Age | Gender | ClassID | TeacherID |
+-------+------------+-----+--------+---------+-----------+
|    26 | Sun Wukong |  35 | F      |    NULL |      NULL |
+-------+------------+-----+--------+---------+-----------+

五、再次对数据库做增量备份

[[email protected] ~]# mariabackup --user=root --password=‘‘ --backup --incremental-basedir=/data/backup/inc1 --target-dir=/data/backup/inc2

六、破坏数据库

[[email protected] ~]# rm -rf /data/mysql/*

七、恢复数据库

7.1先对数据库做清理，并停止数据库服务

[[email protected] ~]# rm -rf /data/mysql/*
[[email protected] ~]# service mysqld stop
Stopping mysqld (via systemctl):                           [  OK  ]

7.2对完全备份做预整理
因为后续还有增量备份，所以此处需要使用apply-log-only选项来阻止事务的回滚。

[[email protected] ~]# mariabackup --prepare --apply-log-only --target-dir=/data/backup/full

7.3合并第一次的增量备份
此为第一个增量备份后续还有第二个增量所以需要使用apply-log-only阻止回滚事务

[[email protected] backup]# mariabackup --prepare --apply-log-only --target-dir=/data/backup/full --incremental-dir=/data/backup/inc1

7.3合并第二次的增量备份
此为最后个增量备份无需再使用apply-log-only阻止回滚事务

[[email protected] backup]# mariabackup --prepare --target-dir=/data/backup/full --incremental-dir=/data/backup/inc2

7.4整理完毕将备份复制回数据库

[[email protected] backup]# mariabackup --copy-back --target-dir=/data/backup/full

7.5将数据库内的属主和属组进行更改

[[email protected] backup]# chown -R mysql.mysql /data/mysql/

八、重启服务测试

[[email protected] backup]# service mysqld start
Starting mysqld (via systemctl):                           [  OK  ]

[[email protected] backup]# msyql
MariaDB [hellodb]> select *from students where stuid>25;
+-------+------------+-----+--------+---------+-----------+
| StuID | Name       | Age | Gender | ClassID | TeacherID |
+-------+------------+-----+--------+---------+-----------+
|    26 | Sun Wukong |  35 | F      |    NULL |      NULL |
+-------+------------+-----+--------+---------+-----------+
1 row in set (0.00 sec)

MariaDB [hellodb]> select *from teachers where tid>4;
+-----+-------------+-----+--------+
| TID | Name        | Age | Gender |
+-----+-------------+-----+--------+
|   5 | Li Xiaolong |  30 | M      |
+-----+-------------+-----+--------+
1 row in set (0.00 sec)

其他的注意事项

1.在数据恢复之前必须先要停止MySQL服务
2.在还原时MySQL的数据库目录必须为空，否则不会覆盖
3.数据库内容还原后，其属主和属组为root需要手动将其全部改为mysql

原文地址：https://blog.51cto.com/11886307/2389857