数据库授权用户，允许192.168.100.0/24网段可以连接mysql

1. 访问数据库

# 主机测试
[root@node1 ~]# mysql -uroot -p
mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| hellodb            |
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+

2. 创建用户

# 创建用户赋权刷新

mysql> CREATE USER feifa @'192.168.100.%' IDENTIFIED BY 'PASSWORD';

mysql> FLUSH PRIVILEGES;

3. 登录测试

# 使用其他机器登录测试，发现能登陆但是数据库未授权
[root@node3 ~]# hostname -I
192.168.100.132
[root@node3 ~]# yum -y install mysql
[root@node3 ~]# mysql -ufeifa -pPASSWORD -h192.168.100.128
mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
+--------------------+

4.赋权访问数据库

# 回到node1上面对feifa用户进行赋权
mysql> GRANT ALL PRIVILEGES ON hellodb.* TO 'feifa' @'192.168.100.%';

mysql> FLUSH PRIVILEGES;

5.连接测试

# 在node3上查看效果
mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| hellodb            |
| information_schema |
+--------------------+