使用mysqldump实现mysql备份

注意:备份文件和二进制日志文件不能与mysql放在同一磁盘下

节点1

1、节点1上修改mysql配置文件,开起二进制日志保存

这里我将二进制日志放在/data/mysql/目录下,/data/是我创建的另外一个lvm磁盘,本来想直接放在/data/下,发现无法启动mysql,所以建议还是放在/data/mysql中

[root@node1 ~]# mkdir -pv /data/mysql/
[root@node1 ~]# chown mysql:mysql /data/*
[root@node1 mysql]# cd /var/lib/mysql
[root@node1 mysql]# cp -a mysql-bin.000001 mysql-bin.000002 mysql-bin.index /data/mysql/
[root@node1 ~]# vim /etc/my.cnf.d/server.cnf
  [server]
  log_bin=/data/mysql/mysql-bin
[root@node1 ~]# service mariadb restart

2、查看二进制日志的一些信息

[root@node1 ~]# mysql
  MariaDB [(none)]> show master logs;
  +------------------+-----------+
  | Log_name     | File_size |
  +------------------+-----------+
  | mysql-bin.000001 |    264 |
  | mysql-bin.000002 |    245 |
  +------------------+-----------+

3、查看表的存储引擎类型并备份

MariaDB [hellodb]> show table status\G;

如果engine是myisam则备份方案如下,需要对锁表后操作

[root@node1 ~]# mysqldump -uroot --lock-tables --master-data=2 --flush-logs --databases hellodb > /root/hellodb_myis.sql

如果engine是innodb则备份方案如下

[root@node1 ~]# mysqldump -uroot --single-transaction --master-data=2 --flush-logs --databases hellodb > /root/hellodb_inno.sql
--single-transaction:热备
--master-data=2:记录为注释的CHANGE MASTER TO语句
--flush-logs:日志滚动

批量修改表的存储引擎【将得到的结果一次执行即可修改,不建议直接在mysql中修改】

MariaDB [hellodb]> SELECT CONCAT('ALTER TABLE ',table_name,' ENGINE=InnoDB;') FROM information_schema.tables WHERE table_schema='hellodb' AND ENGINE='myisam';

4、修改表内数据

MariaDB [(none)]> use hellodb;
MariaDB [hellodb]> insert into students (Name,Age,Gender,ClassID,TeacherID) values ('caocao',99,'M',6,8);
MariaDB [hellodb]> delete from students where stuid=3;

5、复制备份文件到另一节点

[root@node1 ~]# scp hellodb_inno.sql 192.168.1.114:/root/

节点2

6、在另一个节点进行mysql恢复

修改节点2的配置文件

[root@node2 ~]# mkdir -pv /data/mysql
[root@node2 ~]# vim /etc/my.cnf
  [mysqld] 
  log_bin=/data/mysql/mysql-bin
[root@node2 ~]# chown mysql:mysql /data/*
[root@node2 ~]# chown mysql:mysql /data
[root@node2 ~]# service mariadb start

还原备份文件

[root@node2 ~]# mysql < /root/hellodb_inno.sql
[root@node2 ~]# less hellodb_inno.sql
  -- CHANGE MASTER TO MASTER_LOG_FILE='mysql-bin.000002', MASTER_LOG_POS=245;

根据表中的显示,在备份那一刻,二进制日志mysql-bin.000002,操作到了245

7、在节点2上恢复二进制日志

在节点1上将245之后的二进制日志文件转换为sql文件

[root@node1 ~]# mysqlbinlog --start-position=245 /var/lib/mysql/mysql-bin.000002 > binlog.sql

复制给节点2

[root@node1 ~]# scp binlog.sql 192.168.1.114:/root/

利用刚才生产的sql文件来恢复备份之后操作的内容

[root@node2 ~]# mysql < /root/binlog.sql

8、查看恢复情况

[root@node2 ~]# mysql
MariaDB [(none)]> use hellodb;
MariaDB [hellodb]> 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  | 17 | 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 |
|  26 | caocao    | 99 | M   |    6 |     8 |
+-------+---------------+-----+--------+---------+-----------+