为了保障数据的安全，需要定期对数据进行备份。备份的方式有很多种，效果也不一样。一旦数据库中的数据出现了错误，就需要使用备份好的数据进行还原恢复。从而将损失降到最低。下面我们来了解一下MySQL常见的有三种备份恢复方式：
1、利用Mysqldump+二进制日志实现备份
2、利用LVM快照+二进制日志实现备份
3、使用Xtrabackup备份
今天我们主要来了解学习一下使用Xtrabackup进行数据库的增量备份及还原。
1.完全备份
[root@contos7 ~]#mkdir /mysql/backup/{full,inc{1,2}}
[root@contos7 ~]#innobackupex /mysql/backup/full
xtrabackup: recognized server arguments: --datadir=/mysql/data --log_bin=/mysql/logbin --innodb_file_per_table=1
xtrabackup: recognized client arguments: --datadir=/mysql/data --log_bin=/mysql/logbin --innodb_file_per_table=1
181013 15:33:45 innobackupex: Starting the backup operation
IMPORTANT: Please check that the backup run completes successfully.
At the end of a successful backup run innobackupex
prints "completed OK!".
2.第一次修改数据及第一次增量
[root@contos7 ~]#innobackupex --incremental /mysql/backup/inc1 --incremental-basedir=/mysql/backup/full/2018-10-12_11-14-47/
xtrabackup: recognized server arguments: --datadir=/mysql/data --log_bin=/mysql/logbin --innodb_file_per_table=1
xtrabackup: recognized client arguments: --datadir=/mysql/data --log_bin=/mysql/logbin --innodb_file_per_table=1
181013 15:36:07 innobackupex: Starting the backup operation
IMPORTANT: Please check that the backup run completes successfully.
At the end of a successful backup run innobackupex
prints "completed OK!".
3.第二次修改数据及第二次增量
[root@contos7 ~]# innobackupex --incremental /mysql/backup/inc2 --incremental-basedir=/mysql/backup/inc1/2018-10-12_11-16-04/. xtrabackup: recognized server arguments: --datadir=/mysql/data --log_bin=/mysql/logbin --innodb_file_per_table=1 xtrabackup: recognized client arguments: --datadir=/mysql/data --log_bin=/mysql/logbin --innodb_file_per_table=1 181013 15:38:27 innobackupex: Starting the backup operation IMPORTANT: Please check that the backup run completes successfully. At the end of a successful backup run innobackupex prints "completed OK!".
4.对数据库进行破坏
略
5.清空数据停服务
[root@contos7 ~]# systemctl stop mariadb.service
[root@contos7 ~]# rm /mysql/data/* -rf
6.预处理数据库
[root@contos7 ~]# innobackupex --apply-log --redo-only /backup/full/2018-10-12_11-14-47/
[root@contos7 ~]# innobackupex --apply-log --redo-only /backup/full/2018-10-12_11-14-47/ --incremental-dir=/backup/inc1/2018-10-12_11-16-04/
[root@contos7 ~]# innobackupex --apply-log /backup/full/2018-10-12_11-14-47/ --incremental-dir=/backup/inc2/2018-10-12_11-17-00/
7.复制数据
[root@contos7 ~]# innobackupex --copy-back /backup/full/2018-10-12_11-14-47/
8.修改权限和启动服务
[root@contos7 ~]# chown -R mysql.mysql /mysql/data
[root@contos7 ~]# systemctl restart mariadb.service
9.通过二进制日志回恢复recovery，先读取最后一次增量备份目录下的xtrabackup_binlog_info，获取需要恢复的二进制日志的起始位置
[root@contos7 ~]# mysqlbinlog --start-position=8057 /mysql/logbin/mysql-bin.000003 > /root/bin.sql
[root@contos7 ~]# mysql < /root/bin.sql