Mysql之备份工具

一、备份工具

1. mysqldump

mysql服务自带的备份工具；mysqldump备份方式是采用的逻辑备份，其最大的缺陷是备份和恢复速度较慢，如果数据库大于50G，mysqldump备份就不太适合；

InnoDB：热备；启动大事务。

MyISAM：温备；

备份单个数据库hellodb至指定文件
# mysqldump -uroot -h127.0.0.1  -p --databases hellodb >/root/hellodb.sql
Enter password:

备份多个数据库
# mysqldump -uroot -h127.0.0.1  -p --databases hellodb mydb >/root/hellodb-mydb.sql
Enter password:

备份所有数据库
# mysqldump -uroot -h127.0.0.1  -p --all-databases >/root/alldb.sql
Enter password:

2. Xtrabackup

Xtrabackup是由percona提供的mysql数据库备份工具，据官方介绍，这也是世界上惟一一款开源的能够对innodb和xtradb数据库进行热备的工具。

MyISAM：温备，不支持增量备份；InnoDB：热备，增量；

特点：

(1)备份过程快速、可靠；

(2)备份过程不会打断正在执行的事务；

(3)能够基于压缩等功能节约磁盘空间和流量；

(4)自动实现备份检验；

(5)还原速度快；

• 下载
  
  https://www.percona.com/downloads

• 版本

Percona XtraBackup 8.0 支持MySQL8.0的版本；

mysql8.0之前的版本需要使用xtrabackup2.4备份和恢复.

• 安装

# yum install  percona-xtrabackup-24-2.4.26-1.el7.x86_64.rpm
# rpm -ql percona-xtrabackup-24
/usr/bin/innobackupex
/usr/bin/xbcloud
/usr/bin/xbcloud_osenv
/usr/bin/xbcrypt
/usr/bin/xbstream
/usr/bin/xtrabackup
/usr/lib64/xtrabackup/plugin/keyring_file.so
/usr/lib64/xtrabackup/plugin/keyring_vault.so
/usr/share/doc/percona-xtrabackup-24-2.4.26
/usr/share/doc/percona-xtrabackup-24-2.4.26/LICENSE
/usr/share/man/man1/innobackupex.1.gz
/usr/share/man/man1/xbcrypt.1.gz
/usr/share/man/man1/xbstream.1.gz
/usr/share/man/man1/xtrabackup.1.gz

二、备份和恢复

1. 完全备份（mysqldump）+二进制日志文件进行增量恢复

• 先做一次完全备份

# mysqldump -uroot -h127.0.0.1  -p --all-databases >/root/alldb.sql
Enter password:

• 在数据库进行一些修改操作

mysql> DESC students;
+-----------+---------------------+------+-----+---------+----------------+
| Field     | Type                | Null | Key | Default | Extra          |
+-----------+---------------------+------+-----+---------+----------------+
| StuID     | int(10) unsigned    | NO   | PRI | NULL    | auto_increment |
| Name      | varchar(50)         | NO   |     | NULL    |                |
| Age       | tinyint(3) unsigned | NO   |     | NULL    |                |
| Gender    | enum('F','M')       | NO   |     | NULL    |                |
| ClassID   | tinyint(3) unsigned | YES  |     | NULL    |                |
| TeacherID | int(10) unsigned    | YES  |     | NULL    |                |
+-----------+---------------------+------+-----+---------+----------------+
6 rows in set (0.00 sec)

mysql> INSERT INTO students (Name,Age,Gender,ClassID,TeacherID) VALUES ('Chao Gai',47,'m',3,7);
Query OK, 1 row affected (0.00 sec)

mysql> SELECT * FROM students;
+-------+---------------+-----+--------+---------+-----------+
| StuID | Name          | Age | Gender | ClassID | TeacherID |
+-------+---------------+-----+--------+---------+-----------+
|     1 | Shi Zhongyu   |  22 | M      |       2 |         3 |
|     2 | Shi Potian    |  22 | M      |       1 |         7 |
|     4 | Ding Dian     |  32 | M      |       4 |         4 |
|     5 | Yu Yutong     |  26 | M      |       3 |         1 |
|     6 | Shi Qing      |  46 | M      |       5 |      NULL |
|     7 | Xi Ren        |  19 | F      |       3 |      NULL |
|     8 | Lin Daiyu     |  17 | F      |       7 |      NULL |
|     9 | Ren Yingying  |  20 | F      |       6 |      NULL |
|    10 | Yue Lingshan  |  19 | F      |       3 |      NULL |
|    11 | Yuan Chengzhi |  23 | M      |       6 |      NULL |
|    12 | Wen Qingqing  |  19 | F      |       1 |      NULL |
|    13 | Tian Boguang  |  33 | M      |       2 |      NULL |
|    14 | Lu Wushuang   |  21 | F      |       3 |      NULL |
|    15 | Duan Yu       |  19 | M      |       4 |      NULL |
|    16 | Xu Zhu        |  21 | M      |       1 |      NULL |
|    17 | Lin Chong     |  25 | M      |       4 |      NULL |
|    18 | Hua Rong      |  23 | M      |       7 |      NULL |
|    19 | Xue Baochai   |  18 | F      |       6 |      NULL |
|    20 | Diao Chan     |  19 | F      |       7 |      NULL |
|    21 | Huang Yueying |  22 | F      |       6 |      NULL |
|    22 | Xiao Qiao     |  20 | F      |       1 |      NULL |
|    23 | Ma Chao       |  23 | M      |       4 |      NULL |
|    24 | Xu Xian       |  27 | M      |    NULL |      NULL |
|    25 | Sun Dasheng   | 100 | M      |    NULL |      NULL |
|    27 | Jinjiao King  | 100 | M      |    NULL |      NULL |
|    28 | Chao Gai      |  47 | M      |       3 |         7 |
+-------+---------------+-----+--------+---------+-----------+
26 rows in set (0.00 sec)

mysql> DELETE FROM students WHERE StuID=3;
Query OK, 0 rows affected (0.00 sec)

mysql> SELECT * FROM students;
+-------+---------------+-----+--------+---------+-----------+
| StuID | Name          | Age | Gender | ClassID | TeacherID |
+-------+---------------+-----+--------+---------+-----------+
|     1 | Shi Zhongyu   |  22 | M      |       2 |         3 |
|     2 | Shi Potian    |  22 | M      |       1 |         7 |
|     4 | Ding Dian     |  32 | M      |       4 |         4 |
|     5 | Yu Yutong     |  26 | M      |       3 |         1 |
|     6 | Shi Qing      |  46 | M      |       5 |      NULL |
|     7 | Xi Ren        |  19 | F      |       3 |      NULL |
|     8 | Lin Daiyu     |  17 | F      |       7 |      NULL |
|     9 | Ren Yingying  |  20 | F      |       6 |      NULL |
|    10 | Yue Lingshan  |  19 | F      |       3 |      NULL |
|    11 | Yuan Chengzhi |  23 | M      |       6 |      NULL |
|    12 | Wen Qingqing  |  19 | F      |       1 |      NULL |
|    13 | Tian Boguang  |  33 | M      |       2 |      NULL |
|    14 | Lu Wushuang   |  21 | F      |       3 |      NULL |
|    15 | Duan Yu       |  19 | M      |       4 |      NULL |
|    16 | Xu Zhu        |  21 | M      |       1 |      NULL |
|    17 | Lin Chong     |  25 | M      |       4 |      NULL |
|    18 | Hua Rong      |  23 | M      |       7 |      NULL |
|    19 | Xue Baochai   |  18 | F      |       6 |      NULL |
|    20 | Diao Chan     |  19 | F      |       7 |      NULL |
|    21 | Huang Yueying |  22 | F      |       6 |      NULL |
|    22 | Xiao Qiao     |  20 | F      |       1 |      NULL |
|    23 | Ma Chao       |  23 | M      |       4 |      NULL |
|    24 | Xu Xian       |  27 | M      |    NULL |      NULL |
|    25 | Sun Dasheng   | 100 | M      |    NULL |      NULL |
|    27 | Jinjiao King  | 100 | M      |    NULL |      NULL |
|    28 | Chao Gai      |  47 | M      |       3 |         7 |
+-------+---------------+-----+--------+---------+-----------+
26 rows in set (0.00 sec)

恢复数据库

• 先用全备的备份文件导入数据库

# mysql -uroot -h127.0.0.1  -p < alldb.sql
Enter password:

• 查看全量备份时二进制文件的位置792019

# less alldb.sql
...
-- CHANGE MASTER TO MASTER_LOG_FILE='mysql-bin.000001', MASTER_LOG_POS=792019;
...

MASTER_LOG_POS=792019：记录当前二进制文件的位置，也就是从这个事件开始的事件都没有被备份

• 通过mysqlbin把全量备份之后的操作导出到文件

# mysqlbinlog --start-position=792019 /opt/mysql/data/mysql-bin.000001 > binlogbak.sql
# ls
binlogbak.sql

• 通过binlog文件进行增量恢复

# mysql -uroot -h127.0.0.1  -p < binlogbak.sql
Enter password:

• --set-gtid-purged参数

1.Mysqldump中sql_log_bin默认是关闭的。
如果数据要导入主库，可以通过--set-gtid-purged=off备份参数，不会在备份文件中记录SET @@GLOBAL.GTID_PURGED的值。不需要reset master可直接导入。
2.全备的情况下不添加，--set-gtid-purged 默认为ON(常用于重做主从)，部分备份时添加 --set-gtid-purged=off(可在主上做部分恢复，在从上不推荐使用，即便是通过SET @@SESSION.SQL_LOG_BIN= 0;source alldb.sql;的方式导入，之后的数据更新可能会导致复制出现数据已存在的异常。也不适应与备份文件较大的情况。)
`正确的操作是导入从库之后，主从数据可以保持一致，然后reset master;set @@global.gtid_purged='gtid段'; change master to重建复制。`
3.备份文件默认，库是不存在就创建，表是存在就删除重建。
4.对于需要导入主库的场景，建议开启set-gtid-purged=off参数，导入数据时，记录binlog(更新事务号和Position)，不影响复制。
5.对于需要导入从库的场景，建议保持默认或是不设置此参数，导入数据时，不记录binlog。

2. 完全备份（innobackupex）

• 确保表的存储引擎均为innodb

mysql> SHOW TABLE STATUS\G
*************************** 1. row ***************************
           Name: classes
         Engine: InnoDB
        Version: 10
     Row_format: Dynamic
           Rows: 8
 Avg_row_length: 2048
    Data_length: 16384
Max_data_length: 0
   Index_length: 0
      Data_free: 0
 Auto_increment: 9
    Create_time: 2024-03-15 14:40:44
    Update_time: 2024-03-15 14:40:44
     Check_time: NULL
      Collation: utf8_general_ci
       Checksum: NULL
 Create_options:
        Comment:

• 确保每个表使用独立的表空间文件

mysql> SHOW GLOBAL VARIABLES LIKE '%innodb_file_per_table';
+-----------------------+-------+
| Variable_name         | Value |
+-----------------------+-------+
| innodb_file_per_table | ON    |
+-----------------------+-------+
1 row in set (0.00 sec)

• 备份全部数据库（完全备份）

# mkdir /backups/
# innobackupex --user=root --password=PASSWORD --host=127.0.0.1 /backups/
xtrabackup: recognized server arguments: --datadir=/opt/dataengine/mysql/data --server-id=1 --log_bin=mysql-bin
xtrabackup: recognized client arguments:
240316 17:39:13 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!".

240316 17:39:13  version_check Connecting to MySQL server with DSN 'dbi:mysql:;mysql_read_default_group=xtrabackup;host=127.0.0.1;mysql_socket=/opt/dataengine/temp/mysql_client.sock' as 'root'  (using password: YES).
240316 17:39:13  version_check Connected to MySQL server
240316 17:39:13  version_check Executing a version check against the server...
240316 17:39:13  version_check Done.
240316 17:39:13 Connecting to MySQL server host: 127.0.0.1, user: root, password: set, port: not set, socket: /opt/dataengine/temp/mysql_client.sock
Using server version 5.7.26-log
Warning: option 'datadir' has different values:
  '/opt/dataengine/mysql/data' in defaults file
  '/opt/mysql/data/' in SHOW VARIABLES
innobackupex version 2.4.26 based on MySQL server 5.7.35 Linux (x86_64) (revision id: 19de43b)
xtrabackup: uses posix_fadvise().
xtrabackup: cd to /opt/dataengine/mysql/data
xtrabackup: open files limit requested 0, set to 1024
xtrabackup: using the following InnoDB configuration:
xtrabackup:   innodb_data_home_dir = .
xtrabackup:   innodb_data_file_path = ibdata1:12M:autoextend
xtrabackup:   innodb_log_group_home_dir = ./
...
# ls /backups/
2024-03-16_17-37-28  2024-03-16_17-38-11  2024-03-16_17-39-13

• 数据恢复之前需要进行数据整理

# innobackupex --user=root --password=PASSWORD --host=127.0.0.1 --apply-log  /backups/2024-03-16_17-39-13/
xtrabackup: recognized server arguments: --innodb_checksum_algorithm=crc32 --innodb_log_checksum_algorithm=strict_crc32 --innodb_data_file_path=ibdata1:12M:autoextend --innodb_log_files_in_group=2 --innodb_log_file_size=50331648 --innodb_fast_checksum=0 --innodb_page_size=16384 --innodb_log_block_size=512 --innodb_undo_directory=./ --innodb_undo_tablespaces=0 --server-id=1 --redo-log-version=1
xtrabackup: recognized client arguments:
240316 17:48:11 innobackupex: Starting the apply-log operation

IMPORTANT: Please check that the apply-log run completes successfully.
           At the end of a successful apply-log run innobackupex
           prints "completed OK!".

innobackupex version 2.4.26 based on MySQL server 5.7.35 Linux (x86_64) (revision id: 19de43b)
xtrabackup: cd to /backups/2024-03-16_17-39-13/
xtrabackup: This target seems to be not prepared yet.
InnoDB: Number of pools: 1
xtrabackup: xtrabackup_logfile detected: size=8388608, start_lsn=(752615560)
xtrabackup: using the following InnoDB configuration for recovery:
xtrabackup:   innodb_data_home_dir = .
xtrabackup:   innodb_data_file_path = ibdata1:12M:autoextend
xtrabackup:   innodb_log_group_home_dir = .
...
InnoDB: FTS optimize thread exiting.
InnoDB: Starting shutdown...
InnoDB: Shutdown completed; log sequence number 752617000
240316 17:48:16 completed OK!

• 还原操作

被还原的数据库服务关闭

# innobackupex --user=root --password=Capinfo@123! --host=127.0.0.1 --copy-back /backups/2024-03-16_17-39-13/
innobackupex: Starting to copy InnoDB log files
innobackupex: in '/backup/2024-03-16_08-17-53'
innobackupex: back to original InnoDB log directory '/mydata/data'
innobackupex: Finished copying back files.

3. 全部备份（innobackupex）+增量备份+恢复

• 创建表插入数据

mysql> CREATE TABLE testdb;
ERROR 1113 (42000): A table must have at least 1 column
mysql> CREATE TABLE testdb(id int);
Query OK, 0 rows affected (0.01 sec)

mysql> INSERT INTO testdb VALUES (1),(10),(99);
Query OK, 3 rows affected (0.01 sec)
Records: 3  Duplicates: 0  Warnings: 0

mysql> SELECT * FROM testdb;
+------+
| id   |
+------+
|    1 |
|   10 |
|   99 |
+------+
3 rows in set (0.00 sec)

• 全备

# innobackupex --user=root --password=PASSWORD! --host=127.0.0.1 /backups/
240316 18:04:53 Executing UNLOCK TABLES
240316 18:04:53 All tables unlocked
240316 18:04:53 [00] Copying ib_buffer_pool to /backups/2024-03-16_18-04-49/ib_buffer_pool
240316 18:04:53 [00]        ...done
240316 18:04:53 Backup created in directory '/backups/2024-03-16_18-04-49/'
MySQL binlog position: filename 'mysql-bin.000001', position '792754'
240316 18:04:53 [00] Writing /backups/2024-03-16_18-04-49/backup-my.cnf
240316 18:04:53 [00]        ...done
240316 18:04:53 [00] Writing /backups/2024-03-16_18-04-49/xtrabackup_info
240316 18:04:53 [00]        ...done
xtrabackup: Transaction log of lsn (752634077) to (752634086) was copied.
240316 18:04:53 completed OK!

# ls /backups/
2024-03-16_18-04-49
# less /backups/2024-03-16_18-04-49/xtrabackup_checkpoints

• 插入数据

mysql> INSERT INTO testdb VALUES(44),(66);
Query OK, 2 rows affected (0.01 sec)
Records: 2  Duplicates: 0  Warnings: 0

mysql> SELECT * FROM testdb;
+------+
| id   |
+------+
|    1 |
|   10 |
|   99 |
|   44 |
|   66 |
+------+
5 rows in set (0.00 sec)

• 在全备的基础上做增量备份

# innobackupex --user=root --password=PASSWORD --host=127.0.0.1 --incremental /backups/ --incremental-basedir=/backups/2024-03-16_18-04-49
xtrabackup: recognized server arguments: --datadir=/opt/dataengine/mysql/data --server-id=1 --log_bin=mysql-bin
xtrabackup: recognized client arguments:
240316 18:14:25 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!".

240316 18:14:25  version_check Connecting to MySQL server with DSN 'dbi:mysql:;mysql_read_default_group=xtrabackup;host=127.0.0.1;mysql_socket=/opt/dataengine/temp/mysql_client.sock' as 'root'  (using password: YES).
240316 18:14:25  version_check Connected to MySQL server
240316 18:14:25  version_check Executing a version check against the server...
240316 18:14:25  version_check Done.
240316 18:14:25 Connecting to MySQL server host: 127.0.0.1, user: root, password: set, port: not set, socket: /opt/dataengine/temp/mysql_client.sock
Using server version 5.7.26-log
Warning: option 'datadir' has different values:
  '/opt/dataengine/mysql/data' in defaults file
  '/opt/mysql/data/' in SHOW VARIABLES
innobackupex version 2.4.26 based on MySQL server 5.7.35 Linux (x86_64) (revision id: 19de43b)
incremental backup from 752634077 is enabled.
xtrabackup: uses posix_fadvise().
xtrabackup: cd to /opt/dataengine/mysql/data
xtrabackup: open files limit requested 0, set to 1024
xtrabackup: using the following InnoDB configuration:
xtrabackup:   innodb_data_home_dir = .
xtrabackup:   innodb_data_file_path = ibdata1:12M:autoextend
xtrabackup:   innodb_log_group_home_dir = ./
xtrabackup:   innodb_log_files_in_group = 2
...
...
240316 18:14:29 Executing UNLOCK TABLES
240316 18:14:29 All tables unlocked
240316 18:14:29 [00] Copying ib_buffer_pool to /backups/2024-03-16_18-14-25/ib_buffer_pool
240316 18:14:29 [00]        ...done
240316 18:14:29 Backup created in directory '/backups/2024-03-16_18-14-25/'
MySQL binlog position: filename 'mysql-bin.000001', position '793022'
240316 18:14:29 [00] Writing /backups/2024-03-16_18-14-25/backup-my.cnf
240316 18:14:29 [00]        ...done
240316 18:14:29 [00] Writing /backups/2024-03-16_18-14-25/xtrabackup_info
240316 18:14:29 [00]        ...done
xtrabackup: Transaction log of lsn (752640085) to (752640094) was copied.
240316 18:14:29 completed OK!

# less /backups/2024-03-16_18-14-25/xtrabackup_checkpoints
backup_type = incremental
from_lsn = 752634077
to_lsn = 752640085
last_lsn = 752640094
compact = 0
recover_binlog_info = 0
flushed_lsn = 4320242

• 整理完全备份

# innobackupex --user=root --password=PASSWORD --host=127.0.0.1 --apply-log --redo-only /backups/2024-03-16_18-04-49/
xtrabackup: starting shutdown with innodb_fast_shutdown = 1
InnoDB: Starting shutdown...
InnoDB: Shutdown completed; log sequence number 752634095
InnoDB: Number of pools: 1
240316 18:21:51 completed OK!

• 先将增量备份整理合并到完全备份，然后做还原

# innobackupex --user=root --password=Capinfo@123! --host=127.0.0.1 --apply-log --redo-only /backups/2024-03-16_18-04-49/ --incremental-dir /backups/2024-03-16_18-14-25/

240316 18:23:53 [01]        ...done
240316 18:23:53 [01] Copying /backups/2024-03-16_18-14-25/mysql/event.MYD to ./mysql/event.MYD
240316 18:23:53 [01]        ...done
240316 18:23:53 [01] Copying /backups/2024-03-16_18-14-25/mysql/ndb_binlog_index.MYI to ./mysql/ndb_binlog_index.MYI
240316 18:23:53 [01]        ...done
240316 18:23:53 [01] Copying /backups/2024-03-16_18-14-25/hive_h3ctest2/db.opt to ./hive_h3ctest2/db.opt
240316 18:23:53 [01]        ...done
240316 18:23:53 [00] Copying /backups/2024-03-16_18-14-25//xtrabackup_binlog_info to ./xtrabackup_binlog_info
240316 18:23:53 [00]        ...done
240316 18:23:53 [00] Copying /backups/2024-03-16_18-14-25//xtrabackup_info to ./xtrabackup_info
240316 18:23:53 [00]        ...done
240316 18:23:53 completed OK!

• 还原

# innobackupex --user=root --password=Capinfo@123! --host=127.0.0.1 --copy-back /backups/2024-03-16_18-04-49/
240316 18:33:11 [00]        ...done
240316 18:33:11 completed OK!

mysql> SELECT * FROM testdb;
+------+
| id   |
+------+
|    1 |
|   10 |
|   99 |
|   44 |
|   66 |
+------+
5 rows in set (0.00 sec)

三、参考

https://www.cnblogs.com/xq-0226/p/11710139.html

https://zhuanlan.zhihu.com/p/448994764