前言：
安装过程不再赘述，直接说问题，mysql的远程连接需要解决两个问题：1.允许root用户远程连接。2.允许任意ip远程连接数据库。当然，在测试和解决问题之前，得首先保证你的数据库与远程主机之间的网络通信没有问题，简单的来说，就是互相ping通，其次，为了避免防火墙的干扰，将本地主机和数据库主机的防火墙都关闭，当然，生产环境下防火墙肯定是要打开的，并且需要额外的安全配置。
问题解决：
1.新安装的数据库默认是需要初始化的，在数据库服务启动的情况下，使用下面的命令来进行初始化。
[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。
2.允许root用户远程连接与允许任意ip远程连接数据库都是可以通过在数据库里执行一条命令来实现的。
这里分为两种情况：
1）新建admin用户远程连接mysql数据库（新建任意用户，以admin为例）
grant all on *.* to admin@'%' identified by '' with grant option;
flush privileges;
允许任何ip地址(%表示允许任何ip地址)的电脑用admin帐户和密码(123456)来访问这个mysql server。
注意admin账户不一定要存在。
2）支持root用户允许远程连接mysql数据库
grant all privileges on *.* to 'root'@'%' identified by '' with grant option;
flush privileges;
需要注意的是，为root用户配置远程登陆，密码需要和之前配置的密码一致。
3.ubuntu系统的额外配置。
Ubuntu系统的my.cnf文件在vim /etc/mysql/mysql.conf.d/mysqld.cnf中，注释掉其中的
bind-address = 127.0.0.1
centos系统的配置文件中默认没有该行。
检查的办法也很简单，在数据库启动的前提下，使用netstat -an | grep 3306查看端口的连接信息。0.0.0.0则表示允许任意IP连接。
如图所示则为允许任意IP连接。