Centos8上部署MySQL主从备份

虚拟机环境如下：

1.在Node1和Node2上安装数据库；

yum install -y mysql*

2.关闭防火墙服务，关闭开启自启；

systemctl stop firewalld
systemctl disable firewalld

3.开启数据库服务，并设置开机自启；

systemctl start mysqld
systemctl enable mysqld

4.初始化数据库；

mysql_secure_installation     \\初始化mysqld服务
 
 
 
New password:     \\输入设置密码
 
Re-enter new password: 
 
Estimated strength of the password: 100 
Do you wish to continue with the password provided?(Press y|Y for Yes, any other key for No) : y
By default, a MySQL installation has an anonymous user,
allowing anyone to log into MySQL without having to have
a user account created for them. This is intended only for
testing, and to make the installation go a bit smoother.
You should remove them before moving into a production
environment.
 
Remove anonymous users? (Press y|Y for Yes, any other key for No) : 
 
 ... skipping.
 
 
Normally, root should only be allowed to connect from
'localhost'. This ensures that someone cannot guess at
the root password from the network.
 
Disallow root login remotely? (Press y|Y for Yes, any other key for No) : 
 
 ... skipping.
By default, MySQL comes with a database named 'test' that
anyone can access. This is also intended only for testing,
and should be removed before moving into a production
environment.
 
 
Remove test database and access to it? (Press y|Y for Yes, any other key for No) : 
 
 ... skipping.
Reloading the privilege tables will ensure that all changes
made so far will take effect immediately.
 
Reload privilege tables now? (Press y|Y for Yes, any other key for No) : 
 
 ... skipping.
All done! 

5.在Node1虚拟机上，修改配置文件/etc/my.cnf；

vim /etc/my.cnf
 
添加以下内容：
[mysqld]
server-id=1    \\指定ID，主从的两台虚拟机ID必须不同
log-bin=mysql-bin    \\mysql根据配置自动设置指定的二进制文件名

6.在Node1虚拟机上，使用systemctl重启数据库服务；

systemctl restart mysqld

7.在Node1虚拟机上，进入交互模式，配置同步账户。

（1）通过mysql命令进入数据库交互模式；

mysql -uroot -p 
 
\\输入密码

（2）创建同步账户synch；

create user 'synch'@'192.168.100.131' identified by '123456';

（3）授权账户synch；

grant replication slave on *.* to 'synch'@'192.168.100.131';

（4）通过select命令查看用户是否创建成功；

select * from mysql.user where User='synch'\G;

（5）通过show命令检查synch权限；

show grants for 'synch'@'192.168.100.131';

（6）刷新系统权限；

flush privileges;

（7）通过show命令查看当前数据库，即主数据库的状态；

8.在Node2虚拟机上，修改配置文件/etc/my.cnf；

vim /etc/my.cnf 
添加以下内容
[mysqld]
server-id=2
replicate-do-db=test    \\指定要复制的数据库

9.在Node2虚拟机上，使用systemctl重启数据库服务；

systemctl restart mysqld

10.在Node2虚拟机上，进入交互模式，开启同步。

（1）通过mysql命令进入数据库交互模式；

mysql -uroot -p
  \\输入密码

（2）停止同步，默认为开启；

stop slave;

（3）修改MASTER的状态；

change
master to
master_host='192.168.100.130',    \\IP地址为Node1的IP地址
master_port=3306,  
master_user='synch',
master_password='123456',
master_log_file=‘mysql-bin.000002',    \\文件和位置为show master status图片的内容
master_log_pos=1902;

（4）修改完成后，开启同步；

start slave;

11.在Node2数据库上进入交互模式，查看同步状态；

show slave status\G;

在同步状态查看到Slave_IO_Running和Slave_SQL_Running两个状态皆为YES即证明主从数据库配置成功。