备份恢复Percona Xtrabackup

Percona Xtrabackup (物理)

1. 安装

1.1 安装依赖包：

wget -O /etc/yum.repos.d/epel.repo http://mirrors.aliyun.com/repo/epel-7.repo
yum -y install perl perl-devel libaio libaio-devel perl-Time-HiRes perl-DBD-MySQL libev

1.2 下载软件并安装

wget https://www.percona.com/downloads/XtraBackup/Percona-XtraBackup-2.4.12/binary/redhat/7/x86_64/percona-xtrabackup-24-2.4.12-1.el7.x86_64.rpm

yum -y install percona-xtrabackup-*.rpm

2、备份命令介绍:

xtrabackup
innobackupex    ******

3. 备份恢复方式——物理备份

备份流程: 
-- INNODB 
(1) 进行 checkpoint,将内存已经提交事务的脏页,刷新到磁盘ibd文件,并且 记录LSN .
(2) 拷贝InnoDB数据(ibd,frm,ibdata1)文件到预定的备份路径.

-- NO-INNODB
(1) FLUSH TABLE WITH READ LOCK(FTWRL) Global READ LOCK
(2) 拷贝非InnoDB表各种数据 
(3) 解锁
-- REDO
自动将备份期间的redo变化保存下来.并记录全新的LSN号码.


恢复流程: 
    1. prepare  准备过程
      (1) redo将变化前滚 
      (2) Undo将未提交的事务进行回滚
    
    2. copy-back 恢复过程 
        cp 
        --copy-back
        授权

4. 备份策略介绍

full + inc + binlog  : 全备+增量+binlog
full + binlog        :全备+日志

5. xbk备份工具使用

5.1 全备

[root@db01 backup]# innobackupex  --user=root --password=123 /data/backup

5.2 全备自定制目录名

[root@db01 backup]# innobackupex  --user=root --password=123 --no-timestamp /data/backup/full_`date +%F`

5.3 备份信息介绍

xtrabackup_binlog_info :  
mysql-bin.000003    4432    411148c1-26bf-11ea-a420-000c298780da:1-32
作用: 二进制日志截取的起点位置.

xtrabackup_checkpoints :
backup_type = full-backuped   
from_lsn = 0
to_lsn = 227111469
last_lsn = 227111478
compact = 0
recover_binlog_info = 0

xtrabackup_info
xtrabackup_logfile

5.4 增量备份

(1) 模拟周一白天数据变化:
create database xbk charset utf8mb4;
use xbk;
create table t1 (id int);
create table t2 (id int);
create table t3 (id int);
insert into t1 values(1);
commit;
insert into t2 values(1);
commit;
insert into t3 values(1);
commit;

(2) 模拟周一晚上的增量inc1 
innobackupex  --user=root --password=123 --no-timestamp  --incremental  --incremental-basedir=/data/backup/full_2019-12-27    /data/backup/inc1

(3) 模拟周二白天数据变化
use xbk;
insert into t1 values(2);
commit;
insert into t2 values(2);
commit;
insert into t3 values(2);
commit;

(4) 模拟周二晚上的增量inc2 
innobackupex  --user=root --password=123 --no-timestamp  --incremental  --incremental-basedir=/data/backup/inc1    /data/backup/inc2

(5) 模拟周三白天的数据变化
use xbk;
insert into t1 values(3);
commit;
insert into t2 values(3);
commit;
insert into t3 values(3);
commit;

5.5 故障恢复

[root@db01 ~]# pkill mysqld
[root@db01 ~]# \rm -rf /data/mysql/data_3306/*
恢复思路: 
    1. 找最近的全备 
    2. 所有增量(inc1,inc2)合并全备(/data/backup/full_2019-12-27 )中
    3. 备份的prepare(应用redo和undo)
    4. 恢复备份cp ,改权限
    5. 启动数据库
    6. 截取周二备份到周三故障点的binlog,进行恢复.

1. 增量合并并准备
This option should be used when preparing the base full
backup and when merging all incrementals except the last one. 
各个备份的,lsn能够连续.

(1) base_full 的 prepared --apply-log
[root@db01 ~]# innobackupex --apply-log --redo-only /data/backup/full_2019-12-27


(2) 将inc1 合并到full中
innobackupex --apply-log --redo-only   --incremental-dir=/data/backup/inc1 /data/backup/full_2019-12-27


(3) 将inc2 合并到 full中 
innobackupex --apply-log  --incremental-dir=/data/backup/inc2 /data/backup/full_2019-12-27


(4) 整体备份的prepare.
innobackupex --apply-log  /data/backup/full_2019-12-27


2. 恢复备份 
[root@db01 full_2019-12-27]# cp -a * /data/mysql/data_3306/
[root@db01 full_2019-12-27]# chown -R mysql.mysql /data


3. 启动数据库


4. 截取二进制日志
[root@db01 inc2]# cat /data/backup/inc2/xtrabackup_binlog_info 
mysql-bin.000003    6593    411148c1-26bf-11ea-a420-000c298780da:1-42
[root@db01 inc2]# mysqlbinlog --skip-gtids --include-gtids='411148c1-26bf-11ea-a420-000c298780da:43-45' /data/mysql/binlog_3306/mysql-bin.000003 >/data/backup/bin.sql


5. 恢复binlog
mysql> set sql_log_bin=0;
mysql> source /data/backup/bin.sql
mysql> set sql_log_bin=1;

6. 总备份2T,误删除1G一张核心表.

思路: 表空间迁移.