一 文章回顾
在上一篇文章,我们讲到percona-xtrabackup软件的使用,这一篇文章我们讲解percona-xtrabackup实现增量备份及恢复。
二 增量备份示意图
三 percona-xtrabackup实现增量备份及恢复原理
首先,使用percona-xtrabackup工具对数据库进行全备,然后再每次数据库的数据更新后对数据进行增量备份,每次增量备份均在上一次备份的基础上。恢复时依次把每次增量备份的数据恢复到全备中,最后使用合并的数据进行数据恢复。
四 percona-xtrabackup实现增量备份及恢复
第一步,全备
[root@serv01 databackup]# innobackupex --user=root --password=123456 /databackup/
第二步,查看数据
mysql> use larrydb; Database changed mysql> select * from class; +------+-------+ | cid | cname | +------+-------+ | 1 | linux | | 2 | dab | | 3 | Devel | +------+-------+ 3 rows in set (0.00 sec) mysql> select * from stu; +------+----------+------+ | sid | sname | cid | +------+----------+------+ | 1 | larry007 | 1 | +------+----------+------+ 1 row in set (0.00 sec)
第三步,更新数据
mysql> insert into stu values(2,'larry02',1); Query OK, 1 row affected (0.00 sec) mysql> select * from stu; +------+----------+------+ | sid | sname | cid | +------+----------+------+ | 1 | larry007 | 1 | | 2 | larry02 | 1 | +------+----------+------+ 2 rows in set (0.00 sec)
第四步,增量备份,进行了全备和第一次增量备份,所以有两个备份文件夹。我们每次增量备份都是针对上一次备份。
#--incremental:增量备份的文件夹 #--incremental-dir:针对哪个做增量备份 [root@serv01 databackup]# innobackupex --user=root --password=123456 --incremental /databackup/ --incremental-dir /databackup/2013-09-10_22-12-50/ InnoDB Backup Utility v1.5.1-xtrabackup; Copyright 2003, 2009 Innobase Oy and Percona Inc 2009-2012. All Rights Reserved. …… innobackupex: Backup created in directory '/databackup/2013-09-10_22-15-45' innobackupex: MySQL binlog position: filename 'mysql-bin.000004', position 353 130910 22:16:04 innobackupex: completed OK! [root@serv01 databackup]# ll total 8 drwxr-xr-x. 9 root root 4096 Sep 10 22:13 2013-09-10_22-12-50 drwxr-xr-x. 9 root root 4096 Sep 10 22:16 2013-09-10_22-15-45
第五步,再次插入数据
mysql> insert into stu values(3,'larry03',1); Query OK, 1 row affected (0.00 sec) mysql> select * from stu; +------+----------+------+ | sid | sname | cid | +------+----------+------+ | 1 | larry007 | 1 | | 2 | larry02 | 1 | | 3 | larry03 | 1 | +------+----------+------+ 3 rows in set (0.00 sec)
第六步,再次增量备份
[root@serv01 databackup]# ll total 8 drwxr-xr-x. 9 root root 4096 Sep 10 22:13 2013-09-10_22-12-50 drwxr-xr-x. 9 root root 4096 Sep 10 22:16 2013-09-10_22-15-45 [root@serv01 databackup]# innobackupex --user=root --password=123456 --incremental /databackup/ --incremental-dir /databackup/2013-09-10_22-15-45/
第七步,再次插入数据
mysql> insert into stu values(4,'larry04',1); Query OK, 1 row affected (0.00 sec) mysql> select * from stu; +------+----------+------+ | sid | sname | cid | +------+----------+------+ | 1 | larry007 | 1 | | 2 | larry02 | 1 | | 3 | larry03 | 1 | | 4 | larry04 | 1 | +------+----------+------+ 4 rows in set (0.00 sec)
第八步,再次增量备份。一次全备,三次增量备份,所以有四个备份文件夹
[root@serv01 databackup]# innobackupex --user=root --password=123456 --incremental /databackup/ --incremental-dir /databackup/2013-09-10_22-19-21/ [root@serv01 databackup]# ll total 16 drwxr-xr-x. 9 root root 4096 Sep 10 22:13 2013-09-10_22-12-50 drwxr-xr-x. 9 root root 4096 Sep 10 22:16 2013-09-10_22-15-45 drwxr-xr-x. 9 root root 4096 Sep 10 22:19 2013-09-10_22-19-21 drwxr-xr-x. 9 root root 4096 Sep 10 22:22 2013-09-10_22-21-42
第九步,模拟数据丢失
mysql> drop database larrydb; Query OK, 2 rows affected (0.02 sec)
第十步,对全部的数据进行检查。可以看到增量备份和全备的文件占用磁盘大小有很大的差别,显然全备占用磁盘空间多,增量备份占用磁盘空间少
[root@serv01 databackup]# innobackupex --apply-log --redo-only /databackup/2013-09-10_22-12-50/ InnoDB Backup Utility v1.5.1-xtrabackup; Copyright 2003, 2009 Innobase Oy and Percona Inc 2009-2012. All Rights Reserved. …… xtrabackup: starting shutdown with innodb_fast_shutdown = 1 130910 22:23:35 InnoDB: Starting shutdown... 130910 22:23:36 InnoDB: Shutdown completed; log sequence number 2098700 130910 22:23:36 innobackupex: completed OK! [root@serv01 databackup]# du -sh ./* 22M ./2013-09-10_22-12-50 1.5M ./2013-09-10_22-15-45 1.5M ./2013-09-10_22-19-21 1.5M ./2013-09-10_22-21-42
第十一步,对第一次做的增量备份数据进行合并到全备份中去
[root@serv01 databackup]# innobackupex --apply-log --redo-only --incremental /databackup/2013-09-10_22-12-50/ --incremental-dir=/databackup/2013-09-10_22-15-45/ InnoDB Backup Utility v1.5.1-xtrabackup; Copyright 2003, 2009 Innobase Oy and Percona Inc 2009-2012. All Rights Reserved. …… innobackupex: Copying '/databackup/2013-09-10_22-15-45/hello/db.opt' to '/databackup/2013-09-10_22-12-50/hello/db.opt' 130910 22:32:26 innobackupex: completed OK!
第十二步,对第二次做的增量备份数据进行合并到全备份中去
[root@serv01 databackup]# innobackupex --apply-log --redo-only --incremental /databackup/2013-09-10_22-12-50/ --incremental-dir=/databackup/2013-09-10_22-19-21/
第十三步,对第三次做的增量备份数据进行合并到全备份中去
[root@serv01 databackup]# innobackupex --apply-log --redo-only --incremental /databackup/2013-09-10_22-12-50/ --incremental-dir=/databackup/2013-09-10_22-21-42/
第十四步,恢复时需要停掉MySQL,所以我们停掉MySQL
[root@serv01 databackup]# /etc/init.d/mysqld stop ERROR! MySQL server PID file could not be found! [root@serv01 databackup]# pkill -9 mysql
第十五步,恢复数据。注意这里指定的文件夹是2013-09-10_22-12-50
[root@serv01 databackup]# innobackupex --copy-back /databackup/2013-09-10_22-12-50/ InnoDB Backup Utility v1.5.1-xtrabackup; Copyright 2003, 2009 Innobase Oy and Percona Inc 2009-2012. All Rights Reserved. This software is published under the GNU GENERAL PUBLIC LICENSE Version 2, June 1991. IMPORTANT: Please check that the copy-back run completes successfully. At the end of a successful copy-back run innobackupex prints "completed OK!". Original data directory is not empty! at /usr/bin/innobackupex line 571.#报以上错需要删除数据目录下的东西[root@serv01 data]# pwd /usr/local/mysql/data [root@serv01 data]# ls game ib_logfile0 mysql mysql-bin.000003 performance_schema test hello ib_logfile1 mysql-bin.000001 mysql-bin.000004 serv01.host.com.err xtrabackup_binlog_pos_innodb ibdata1 mnt mysql-bin.000002 mysql-bin.index serv01.host.com.pid [root@serv01 data]# rm -rf *#再次恢复数据,并更改数据库数据目录的拥有者和所属组[root@serv01 databackup]# innobackupex --copy-back /databackup/2013-09-10_22-12-50/ [root@serv01 data]# ll total 18464 drwxr-xr-x. 2 root root 4096 Sep 10 22:37 game drwxr-xr-x. 2 root root 4096 Sep 10 22:37 hello -rw-r-----. 1 root root 18874368 Sep 10 22:33 ibdata1 drwxr-xr-x. 2 root root 4096 Sep 10 22:37 larrydb drwxr-xr-x. 2 root root 4096 Sep 10 22:37 mnt drwxr-xr-x. 2 root root 4096 Sep 10 22:37 mysql drwxr-xr-x. 2 root root 4096 Sep 10 22:37 performance_schema drwxr-xr-x. 2 root root 4096 Sep 10 22:37 test -rw-r--r--. 1 root root 24 Sep 10 22:37 xtrabackup_binlog_pos_innodb [root@serv01 data]# chown mysql.mysql /usr/local/mysql/data/ -R
第十六步,启动服务
[root@serv01 data]# /etc/init.d/mysqld start Starting MySQL.. SUCCESS!
第十七步,登录数据库,然后查看数据
[root@serv01 data]# mysql -uroot -p123456 mysql> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | game | | hello | | larrydb | | mnt | | mysql | | performance_schema | | test | +--------------------+ 8 rows in set (0.00 sec) mysql> select * from larrydb.class; +------+-------+ | cid | cname | +------+-------+ | 1 | linux | | 2 | dab | | 3 | Devel | +------+-------+ 3 rows in set (0.00 sec) mysql> select * from larrydb.stu; +------+----------+------+ | sid | sname | cid | +------+----------+------+ | 1 | larry007 | 1 | | 2 | larry02 | 1 | | 3 | larry03 | 1 | | 4 | larry04 | 1 | +------+----------+------+ 4 rows in set (0.00 sec)