Xtrabackup 全备和还原以及增量备份和还原

目录

• MySQL环境介绍
• 全备和还原
  • 准备备份目录
  • 创建测试数据
  • 全量备份
  • 模拟删除数据
  • 还原数据操作
    • 第一步 备份备份文件
    • 第二步 关闭数据库
    • 第三步 移除数据库的data目录
    • 第四步 恢复前准备
    • 第五步 恢复数据
    • 第六步 授权data目录启动MySQL
    • 第七步 验证数据恢复操作

本文继Xtrabackup安装和参数详解，本次介绍全备和还原以及增量备份和还原

MySQL环境介绍

阿里云云主机

系统信息以及数据库版本，数据存放目录具体如下：

[root@node ~]# uname -r
4.18.16-1.el7.elrepo.x86_64
[root@node ~]# cat /etc/redhat-release 
CentOS Linux release 7.4.1708 (Core) 
[root@node ~]# /opt/mysql/bin/mysql -V
/opt/mysql/bin/mysql  Ver 14.14 Distrib 5.6.39, for linux-glibc2.12 (x86_64) using  EditLine wrapper
[root@node ~]# ls /opt/mysql/data/
auto.cnf  ibdata1  ib_logfile0  ib_logfile1  mysql  performance_schema  test
[root@node ~]# ls -ld /opt/mysql/my.cnf 
-rw-r--r-- 1 mysql mysql 1468 Dec  6 21:37 /opt/mysql/my.cnf

全备和还原

准备备份目录

[root@node ~]# cd /opt/
[root@node opt]# ls
mysql  mysql-5.6  src
[root@node opt]# mkdir backup/{full,incr} -p
[root@node opt]# ls backup/
full  incr

1. full： 文件中存放全量备份
2. incr： 文件中存放增量备份

创建测试数据

创建一个测试数据库，库名为：xtra_test

在xtra_test库中，创建一个friends表，字段只有id和name，并插入一条数据

具体操作如下：

[root@node opt]# mysql -uroot -p234567
Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or g.
Your MySQL connection id is 19
Server version: 5.6.39 MySQL Community Server (GPL)

Copyright (c) 2000, 2018, 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> create database xtra_test;
Query OK, 1 row affected (0.00 sec)

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| xtra_test          |
+--------------------+
4 rows in set (0.00 sec)

mysql> use xtra_test;
Database changed
mysql> create table friends (
    -> id int(3) not null,
    -> name varchar(8) not null
    -> );
Query OK, 0 rows affected (0.01 sec)

mysql> show tables;
+---------------------+
| Tables_in_xtra_test |
+---------------------+
| friends             |
+---------------------+
1 row in set (0.00 sec)
mysql> desc friends;
+-------+------------+------+-----+---------+-------+
| Field | Type       | Null | Key | Default | Extra |
+-------+------------+------+-----+---------+-------+
| id    | int(3)     | NO   |     | NULL    |       |
| name  | varchar(8) | NO   |     | NULL    |       |
+-------+------------+------+-----+---------+-------+
2 rows in set (0.00 sec)
mysql> INSERT INTO friends( id, name ) VALUES ( 1, 'jack' ) ;
Query OK, 1 row affected (0.00 sec)

mysql> select * from friends;
+----+------+
| id | name |
+----+------+
|  1 | jack |
+----+------+
1 row in set (0.00 sec)

全量备份

这里的具体参数含义请查看：Xtrabackup安装和参数详解

[root@node opt]# innobackupex --defaults-file=/opt/mysql/my.cnf --user=root --password=234567 /opt/backup/full/
......
181211 11:18:44 [01]        ...done
181211 11:18:44 Finished backing up non-InnoDB tables and files
181211 11:18:44 Executing FLUSH NO_WRITE_TO_BINLOG ENGINE LOGS...
xtrabackup: The latest check point (for incremental): '1645416'
xtrabackup: Stopping log copying thread.
.181211 11:18:44 >> log scanned up to (1645416)

181211 11:18:44 Executing UNLOCK TABLES
181211 11:18:44 All tables unlocked
181211 11:18:44 Backup created in directory '/opt/backup/full/2018-12-11_11-18-42/'
181211 11:18:44 [00] Writing /opt/backup/full/2018-12-11_11-18-42/backup-my.cnf
181211 11:18:44 [00]        ...done
181211 11:18:44 [00] Writing /opt/backup/full/2018-12-11_11-18-42/xtrabackup_info
181211 11:18:44 [00]        ...done
xtrabackup: Transaction log of lsn (1645416) to (1645416) was copied.
181211 11:18:44 completed OK!

最后提示 OK 了，查看备份目录中

[root@node opt]# ls /opt/backup/full/
2018-12-11_11-18-42
[root@node opt]# ls /opt/backup/full/2018-12-11_11-18-42/
backup-my.cnf  ibdata1  mysql  performance_schema  xtrabackup_binlog_info  xtrabackup_checkpoints  xtrabackup_info  xtrabackup_logfile  xtra_test

备份完后，备份目录下有几个文件需要注意：

xtrabackup_binlog_info

记录了binlog的position，若开启了GTID，也会将GTID取出。在用于备份+binlog恢复或建立slave的场景里十分有用
注意 如果MySQL没有开启log-bin参数，则不会生产次文件

backup-my.cnf

记录了备份时可能涉及到的选项参数，比如系统表空间信息，独立undo表空间信息，redo-log信息等

xtrabackup_checkpoints

记录了此次备份的类型和lsn号的起始值，是否压缩等

xtrabackup_info

记录了备份工具的信息，时间，备份对象（是针对全实例还是某库表），是否是增量，binlog位置等

模拟删除数据

直接删除xtra_test数据库；

此操作为模拟，请勿真是在线上操作

[root@node opt]# mysql -uroot -p234567
Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or g.
Your MySQL connection id is 4
Server version: 5.6.39-log MySQL Community Server (GPL)

Copyright (c) 2000, 2018, 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> drop database xtra_test;
Query OK, 1 row affected (0.01 sec)

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
+--------------------+
3 rows in set (0.00 sec)

还原数据操作

还原步骤：

1. 先把xtrabackup备份下来的目录进行再次备份，防止在还原的时候误操作，导致备份不可用；
2. 关闭要回复的数据库实例；
3. 移除需要恢复数据的MySQL实例下的data目录，建议mv移动到别的目录下；
4. 使用--apply-log 参数进行恢复前准备操作，如事物回滚等操作；
5. 使用--copy-back 和 --rsync 参数进行恢复；
6. 授权MySQL实例下的data目录后，启动数据库
7. 验证恢复数据

第一步 备份备份文件

[root@node ~]# cd /opt/backup/full/
[root@node full]# ls
2018-12-11_14-04-15
[root@node full]# cp -a 2018-12-11_14-04-15 2018-12-11_14-04-15_back
[root@node full]# ll
total 8
drwxr-x--- 5 root root 4096 Dec 11 14:04 2018-12-11_14-04-15
drwxr-x--- 5 root root 4096 Dec 11 14:04 2018-12-11_14-04-15_back

第二步 关闭数据库

[root@node full]# /etc/init.d/mysqld  stop
Shutting down MySQL.. 
[root@node full]# ps aux|grep mysql
root     19368  0.0  0.1 112720  2232 pts/1    S+   15:01   0:00 grep --color=auto mysql
[root@node full]# netstat -lntup | grep 3306

第三步 移除数据库的data目录

[root@node full]# mv /opt/mysql/data /tmp/
[root@node full]# ls -ld /opt/mysql/data
ls: cannot access /opt/mysql/data: No such file or directory
[root@node full]# ls /tmp/data/
auto.cnf  ibdata1  ib_logfile0  ib_logfile1  mysql  mysql-bin.000001  mysql-bin.index  performance_schema

第四步 恢复前准备

[root@node full]# innobackupex --defaults=/opt/mysql/my.cnf --apply-log /opt/backup/full/2018-12-11_14-04-15/
.......
InnoDB: Renaming log file ./ib_logfile101 to ./ib_logfile0
InnoDB: New log files created, LSN=1654036
InnoDB: Highest supported file format is Barracuda.
InnoDB: Log scan progressed past the checkpoint lsn 1654284
InnoDB: Doing recovery: scanned up to log sequence number 1654293 (0%)
InnoDB: Database was not shutdown normally!
InnoDB: Starting crash recovery.
InnoDB: xtrabackup: Last MySQL binlog file position 635, file name mysql-bin.000001
InnoDB: Removed temporary tablespace data file: "ibtmp1"
InnoDB: Creating shared tablespace for temporary tables
InnoDB: Setting file './ibtmp1' size to 12 MB. Physically writing the file full; Please wait ...
InnoDB: File './ibtmp1' size is now 12 MB.
InnoDB: 96 redo rollback segment(s) found. 1 redo rollback segment(s) are active.
InnoDB: 32 non-redo rollback segment(s) are active.
InnoDB: Waiting for purge to start
InnoDB: 5.7.19 started; log sequence number 1654293
xtrabackup: starting shutdown with innodb_fast_shutdown = 1
InnoDB: FTS optimize thread exiting.
InnoDB: Starting shutdown...
InnoDB: Shutdown completed; log sequence number 1654312
181211 14:42:07 completed OK!
[root@node full]# ls 2018-12-11_14-04-15/ -l
total 294956
-rw-r----- 1 root root       481 Dec 11 14:04 backup-my.cnf
-rw-r----- 1 root root  12582912 Dec 11 14:42 ibdata1
-rw-r----- 1 root root 134217728 Dec 11 14:42 ib_logfile0
-rw-r----- 1 root root 134217728 Dec 11 14:42 ib_logfile1
-rw-r----- 1 root root  12582912 Dec 11 14:42 ibtmp1
drwxr-x--- 2 root root      4096 Dec 11 14:04 mysql
drwxr-x--- 2 root root      4096 Dec 11 14:04 performance_schema
-rw-r----- 1 root root        21 Dec 11 14:04 xtrabackup_binlog_info
-rw-r--r-- 1 root root        21 Dec 11 14:42 xtrabackup_binlog_pos_innodb
-rw-r----- 1 root root       113 Dec 11 14:42 xtrabackup_checkpoints
-rw-r----- 1 root root       509 Dec 11 14:04 xtrabackup_info
-rw-r----- 1 root root   8388608 Dec 11 14:42 xtrabackup_logfile
-rw-r--r-- 1 root root         1 Dec 11 14:42 xtrabackup_master_key_id
drwxr-x--- 2 root root      4096 Dec 11 14:04 xtra_test

注意文件时间的变化，说明准备全备文件的操作只是对备份集本身做了相关处理，所以在准备恢复前最好对备份集再次备份

第五步 恢复数据

[root@node full]# innobackupex --defaults-file=/opt/mysql-5.6/my.cnf --copy-back /opt/backup/full/2018-12-11_14-04-15/
......
181211 15:02:41 [01]        ...done
181211 15:02:41 [01] Copying ./performance_schema/events_statements_summary_by_thread_by_event_name.frm to /opt/mysql/data/performance_schema/events_statements_summary_by_thread_by_event_name.frm
181211 15:02:41 [01]        ...done
181211 15:02:41 [01] Copying ./performance_schema/mutex_instances.frm to /opt/mysql/data/performance_schema/mutex_instances.frm
181211 15:02:41 [01]        ...done
181211 15:02:41 [01] Copying ./performance_schema/events_waits_summary_global_by_event_name.frm to /opt/mysql/data/performance_schema/events_waits_summary_global_by_event_name.frm
181211 15:02:41 [01]        ...done
181211 15:02:41 [01] Copying ./xtrabackup_info to /opt/mysql/data/xtrabackup_info
181211 15:02:41 [01]        ...done
181211 15:02:41 [01] Copying ./xtrabackup_master_key_id to /opt/mysql/data/xtrabackup_master_key_id
181211 15:02:41 [01]        ...done
181211 15:02:41 completed OK!
[root@node full]# ls /opt/mysql/data/ -l
total 286748
-rw-r----- 1 root root  12582912 Dec 11 15:02 ibdata1
-rw-r----- 1 root root 134217728 Dec 11 15:02 ib_logfile0
-rw-r----- 1 root root 134217728 Dec 11 15:02 ib_logfile1
-rw-r----- 1 root root  12582912 Dec 11 15:02 ibtmp1
drwxr-x--- 2 root root      4096 Dec 11 15:02 mysql
drwxr-x--- 2 root root      4096 Dec 11 15:02 performance_schema
-rw-r----- 1 root root        21 Dec 11 15:02 xtrabackup_binlog_pos_innodb
-rw-r----- 1 root root       509 Dec 11 15:02 xtrabackup_info
-rw-r----- 1 root root         1 Dec 11 15:02 xtrabackup_master_key_id
drwxr-x--- 2 root root      4096 Dec 11 15:02 xtra_test

第六步 授权data目录启动MySQL

[root@node full]# ls -l /opt/mysql/data/
total 286748
-rw-r----- 1 mysql mysql  12582912 Dec 11 15:02 ibdata1
-rw-r----- 1 mysql mysql 134217728 Dec 11 15:02 ib_logfile0
-rw-r----- 1 mysql mysql 134217728 Dec 11 15:02 ib_logfile1
-rw-r----- 1 mysql mysql  12582912 Dec 11 15:02 ibtmp1
drwxr-x--- 2 mysql mysql      4096 Dec 11 15:02 mysql
drwxr-x--- 2 mysql mysql      4096 Dec 11 15:02 performance_schema
-rw-r----- 1 mysql mysql        21 Dec 11 15:02 xtrabackup_binlog_pos_innodb
-rw-r----- 1 mysql mysql       509 Dec 11 15:02 xtrabackup_info
-rw-r----- 1 mysql mysql         1 Dec 11 15:02 xtrabackup_master_key_id
drwxr-x--- 2 mysql mysql      4096 Dec 11 15:02 xtra_test
[root@node full]# /etc/init.d/mysqld  start
Starting MySQL..                                           [  OK  ]
[root@node full]# ps aux|grep mysql
root     19450  0.0  0.1 113324  3196 pts/1    S    15:04   0:00 /bin/sh /opt/mysql/bin/mysqld_safe --datadir=/opt/mysql/data --pid-file=/opt/mysql/mysqld.pid
mysql    20257  2.2 44.1 2299484 901804 pts/1  Sl   15:04   0:00 /opt/mysql/bin/mysqld --basedir=/opt/mysql --datadir=/opt/mysql/data --plugin-dir=/opt/mysql/lib/plugin --user=mysql --log-error=/opt/mysql/error.log --open-files-limit=4161 --pid-file=/opt/mysql/mysqld.pid --socket=/tmp/mysql.sock --port=3306
root     20288  0.0  0.1 112720  2244 pts/1    S+   15:04   0:00 grep --color=auto mysql
[root@node full]# netstat -lntup | grep 3306
tcp6       0      0 :::3306                 :::*                    LISTEN      20257/mysqld 

第七步 验证数据恢复操作

[root@node full]# mysql -uroot -p234567
Warning: Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or g.
Your MySQL connection id is 1
Server version: 5.6.39-log MySQL Community Server (GPL)

Copyright (c) 2000, 2018, 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> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| xtra_test          |
+--------------------+
4 rows in set (0.00 sec)

mysql> use xtra_test;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A

Database changed
mysql> show tables;
+---------------------+
| Tables_in_xtra_test |
+---------------------+
| friends             |
+---------------------+
1 row in set (0.00 sec)

mysql> select * from friends;
+----+------+
| id | name |
+----+------+
|  1 | jack |
+----+------+
1 row in set (0.01 sec

至此，全量备份和还原完成；