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利用binlog进行数据库的还原

前言:在学习mysql备份的时候,深深的感受到mysql的备份还原功能没有oracle强大;比如一个很常见的恢复场景:基于时间点的恢复,oracle通过rman工具就能够很快的实现数据库的恢复,但是mysql在进行不完全恢复的时候很大的一部分要依赖于mysqlbinlog这个工具运行binlog语句来实现,本文档介绍通过mysqlbinlog实现各种场景的恢复;

二、测试步骤说明:

数据库的插入准备工作

2.1 在时间点<b>A</b>进行一个数据库的完整备份;

2.2 在时间点<b>B</b>创建一个数据库BKT,并在BKT下面创建一个表JOHN,并插入5条数据;

2.3 在时间点<b>C</b>往表JOHN继续插入数据到10条;

数据库的恢复工作

2.4 恢复数据库到时间点<b>A</b><b>,</b>然后检查数据库表的状态;

2.5 恢复数据库到时间点<b>B</b>,检查相应的系统状态;

2.6 恢复数据库到时间点<b>C</b>,并检查恢复的状态;

三、场景模拟测试步骤(备份恢复是一件很重要的事情)

3.1 执行数据库的全备份;

点击(此处)折叠或打开

[root@mysql01 backup]# mysqlbackup --user=root --password --backup-dir=/backup backup-and-apply-log //运行数据库的完整备份

3.2 创建数据库、表并插入数据

mysql&gt; SELECT CURRENT_TIMESTAMP;

+---------------------+

| CURRENT_TIMESTAMP |

| 2014-11-26 17:51:27 |

1 row in set (0.01 sec)

mysql&gt; show databases; //尚未创建数据库BKT

+--------------------+

| Database |

| information_schema |

| john |

| mysql |

| performance_schema |

4 rows in set (0.03 sec)

mysql&gt; Ctrl-C --

Aborted

[root@mysql02 data]# mysql -uroot -p

Enter password:

Welcome to the MySQL monitor. Commands end with ; or \\g.

Your MySQL connection id is 2

Server version: 5.5.36-log Source distribution

Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its

affiliates. Other names may be trademarks of their respective

owners.

Type \'help;\' or \'\\h\' for help. Type \'\\c\' to clear the current input statement.

mysql&gt; show master status;

+------------------+----------+--------------+------------------+

| File | Position | Binlog_Do_DB | Binlog_Ignore_DB |

| mysql-bin.000001 | 107 | | | //当前数据库log的pos状态

1 row in set (0.00 sec)

mysql&gt; SELECT CURRENT_TIMESTAMP; //当前的时间戳 当前时间点A

| 2014-11-26 17:54:12 |

mysql&gt; create database BKT; //创建数据库BKT

Query OK, 1 row affected (0.01 sec)

mysql&gt; create table john (id varchar(32));

ERROR 1046 (3D000): No database selected

mysql&gt; use bkt;

ERROR 1049 (42000): Unknown database \'bkt\'

mysql&gt; use BKT;

Database changed

Query OK, 0 rows affected (0.02 sec)

mysql&gt; insert into john values(\'1\');

mysql&gt; insert into john values(\'2\');

mysql&gt; insert into john values(\'3\');

Query OK, 1 row affected (0.00 sec)

mysql&gt; insert into john values(\'4\');

mysql&gt; insert into john values(\'5\');

mysql&gt; SELECT CURRENT_TIMESTAMP; //插入5条数据后数据库的时间点B,记录该点便于数据库的恢复

| 2014-11-26 17:55:53 |

| mysql-bin.000001 | 1204 | | | //当前binlog的pos位置

 3.3 设置时间点C的测试

mysql&gt; insert into john values(\'6\');

Query OK, 1 row affected (0.02 sec)

mysql&gt; insert into john values(\'7\');

mysql&gt; insert into john values(\'8\');

mysql&gt; insert into john values(\'9\');

mysql&gt; insert into john values(\'10\');

Query OK, 1 row affected (0.03 sec)

| mysql-bin.000001 | 2125 | | |

| 2014-11-26 17:58:08 |

 3.4 以上的操作完成之后,便可以执行数据库的恢复测试

[root@mysql02 data]# mysqlbackup --defaults-file=/backup/server-my.cnf --datadir=/data/mysql --backup-dir=/backup/ copy-back

MySQL Enterprise Backup version 3.11.0 Linux-3.8.13-16.2.1.el6uek.x86_64-x86_64 [2014/08/26]

Copyright (c) 2003, 2014, Oracle and/or its affiliates. All Rights Reserved.

 mysqlbackup: INFO: Starting with following command line ...

 mysqlbackup --defaults-file=/backup/server-my.cnf --datadir=/data/mysql

        --backup-dir=/backup/ copy-back

 mysqlbackup: INFO:

IMPORTANT: Please check that mysqlbackup run completes successfully.

           At the end of a successful \'copy-back\' run mysqlbackup

           prints \"mysqlbackup completed OK!\".

141126 17:59:58 mysqlbackup: INFO: MEB logfile created at /backup/meta/MEB_2014-11-26.17-59-58_copy_back.log

--------------------------------------------------------------------

                       Server Repository Options:

  datadir = /data/mysql

  innodb_data_home_dir = /data/mysql

  innodb_data_file_path = ibdata1:10M:autoextend

  innodb_log_group_home_dir = /data/mysql/

  innodb_log_files_in_group = 2

  innodb_log_file_size = 5242880

  innodb_page_size = Null

  innodb_checksum_algorithm = none

                       Backup Config Options:

  datadir = /backup/datadir

  innodb_data_home_dir = /backup/datadir

  innodb_log_group_home_dir = /backup/datadir

  innodb_page_size = 16384

 mysqlbackup: INFO: Creating 14 buffers each of size 16777216.

141126 17:59:58 mysqlbackup: INFO: Copy-back operation starts with following threads

        1 read-threads 1 write-threads

 mysqlbackup: INFO: Could not find binlog index file. If this is online backup then server may not have started with --log-bin.

        Hence, binlogs will not be copied for this backup. Point-In-Time-Recovery will not be possible.

141126 17:59:58 mysqlbackup: INFO: Copying /backup/datadir/ibdata1.

 mysqlbackup: Progress in MB: 200 400 600

141126 18:00:22 mysqlbackup: INFO: Copying the database directory \'john\'

141126 18:00:23 mysqlbackup: INFO: Copying the database directory \'mysql\'

141126 18:00:23 mysqlbackup: INFO: Copying the database directory \'performance_schema\'

141126 18:00:23 mysqlbackup: INFO: Completing the copy of all non-innodb files.

141126 18:00:23 mysqlbackup: INFO: Copying the log file \'ib_logfile0\'

141126 18:00:23 mysqlbackup: INFO: Copying the log file \'ib_logfile1\'

141126 18:00:24 mysqlbackup: INFO: Creating server config files server-my.cnf and server-all.cnf in /data/mysql

141126 18:00:24 mysqlbackup: INFO: Copy-back operation completed successfully.

141126 18:00:24 mysqlbackup: INFO: Finished copying backup files to \'/data/mysql\'

mysqlbackup completed //数据库恢复完成

 授权并打开数据库

[root@mysql02 data]# chmod -R 777 mysql //需要授权后才能打开

[root@mysql02 data]# cd mysql

[root@mysql02 mysql]# ll

总用量 733220

-rwxrwxrwx. 1 root root 305 11月 26 18:00 backup_variables.txt

-rwxrwxrwx. 1 root root 740294656 11月 26 18:00 ibdata1

-rwxrwxrwx. 1 root root 5242880 11月 26 18:00 ib_logfile0

-rwxrwxrwx. 1 root root 5242880 11月 26 18:00 ib_logfile1

drwxrwxrwx. 2 root root 4096 11月 26 18:00 john

drwxrwxrwx. 2 root root 4096 11月 26 18:00 mysql

drwxrwxrwx. 2 root root 4096 11月 26 18:00 performance_schema

-rwxrwxrwx. 1 root root 8488 11月 26 18:00 server-all.cnf

-rwxrwxrwx. 1 root root 1815 11月 26 18:00 server-my.cnf //没有BKT数据库

[root@mysql02 mysql]# service mysqld start //启动数据库

 3.5 进行数据库的恢复到时间点B

[root@mysql02 mysql2]# pwd //备份的时候,需要备份binlog日志,之前的binlog目录为/data/mysql2

/data/mysql2

[root@mysql02 mysql2]# mysqlbinlog --start-position=107 --stop-position=1203 mysql-bin.000001| mysql -uroot -p //根据post的位置进行恢复,当前的pos位置为107,恢复到pos位置到1203

[root@mysql02 mysql2]# mysql -uroot -p

Your MySQL connection id is 3

mysql&gt; show databases;

| BKT |

5 rows in set (0.02 sec)

mysql&gt; use BKT

mysql&gt; show tables;

+---------------+

| Tables_in_BKT |

mysql&gt; select * from john;

+------+

| id |

| 1 |

| 2 |

| 3 |

| 4 |

| 5 |

5 rows in set (0.01 sec) //查看数据库恢复成功

 3.6 恢复数据库到时间点C

[root@mysql02 mysql2]# mysqlbinlog --start-date=\"2014-11-27 09:21:56\" --stop-date=\"2014-11-27 09:22:33\" mysql-bin.000001| mysql -uroot -p123456 //本次通过基于时间点的恢复,恢复到时间点C

Warning: Using unique option prefix start-date instead of start-datetime is deprecated and will be removed in a future release. Please use the full name instead.

Warning: Using unique option prefix stop-date instead of stop-datetime is deprecated and will be removed in a future release. Please use the full name instead.

Your MySQL connection id is 6

5 rows in set (0.00 sec)

| 6 |

| 7 |

| 8 |

| 9 |

| 10 |

10 rows in set (0.00 sec) //经过检查成功恢复到时间点C

四、mysqlbinlog的其他总结:以上是利用binlog文件进行基于<b>时间点</b>和<b>binlog</b>的POS位置恢复的测试,mysqlbinlog的使用还有很多功能,运行mysqlbinlog --help可以查看相应参数;

4.1 查看binlog的内容:[root@mysql02 mysql2]# mysqlbinlog mysql-bin.000001 

4.2 mysqlbinlog的其他常用参数:

-h  根据数据库的IP

-P  根据数据库所占用的端口来分

-server-id 根据数据库serverid来还原(在集群中很有用)

-d  根据数据库名称

例如: [root@mysql02 mysql2]# mysqlbinlog -d BKT mysql-bin.000001 //还原BKT数据库的信息

参数的组合使用:

[root@mysql02 mysql2]# mysqlbinlog --start-date=\"2014-11-27 09:21:56\" --stop-date=\"2014-11-27 09:22:33\" -d BKT -h 127.0.0.1 /var/lib/mysql/mysql-bin.000001 |mysql -u root -p

#如果有多个binlog文件,用逗号隔开;

4.4 恢复是一件很重要的事情,如果不知道具体要恢复的时间点,请把binlog文件先转换成文本文件,详细查看完相应的内容再进行恢复;

[root@mysql02 mysql2]# mysqlbinlog mysql-bin.000001 &gt; /tmp/00001.sql

总结:备份有时候永远都用不上,但是你永远也不知道什么时候会用上,正所谓养兵千日用兵一时,作为一个合格的DBA有个可用的备份,就可以做到胸有成竹;