[root@localhost ~]# mysql_secure_installation

New password:

Re-enter new password:

Password updated successfully!

Reloading privilege tables..

 ... Success!

By default, a MariaDB installation has an anonymous user, allowing anyone

to log into MariaDB 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? [Y/n]

 ... Success!

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? [Y/n] n　　#如果是为root用户配置远程登陆，这里需要选择n，不选择禁止root用户远程登陆，别的选择都无关紧要。

 ... skipping.

By default, MariaDB 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? [Y/n]

 - Dropping test database...

 ... Success!

 - Removing privileges on test database...

 ... Success!

Reloading the privilege tables will ensure that all changes made so far

will take effect immediately.

Reload privilege tables now? [Y/n]

 ... Success!

Cleaning up...

All done!  If you've completed all of the above steps, your MariaDB

installation should now be secure.

Thanks for using MariaDB!
[root@localhost ~]# systemctl restart mariadb　　#完成初始化之后，重启服务。

grant all on *.* to admin@'%' identified by '' with grant option;

flush privileges;

grant all privileges on *.* to 'root'@'%' identified by '' with grant option;

flush privileges;