[mysql] grant remote access of MySQL database from any IP address

To be able to connect with your user from any IP address, do the following:

Allow mysql server to accept remote connections. For this open mysqld.conf file:

sudo gedit /etc/mysql/mysql.conf.d/mysqld.cnf

Search for the line starting with "bind-address" and set it's value to 0.0.0.0

bind-address                    = 0.0.0.0

and finally save the file.

Note: If you’re running MySQL 8+, the bind-address directive will not be in the mysqld.cnf file by default. In this case, add the directive to the bottom of the file /etc/mysql/mysql.conf.d/mysqld.cnf.

Now restart the mysql server, either with systemd or use the older service command. This depends on your operating system:

sudo systemctl restart mysql # for ubuntu    
sudo systemctl restart mysqld.service # for debian

Finally, mysql server is now able to accept remote connections.

Now we need to create a user and grant it permission, so we can be able to login with this user remotely.

Connect to MySQL database as root, or any other user with root privilege.

mysql -u root -p

now create desired user in both localhost and '%' wildcard and grant permissions on all DB's as such .

CREATE USER 'myuser'@'localhost' IDENTIFIED BY 'mypass';
CREATE USER 'myuser'@'%' IDENTIFIED BY 'mypass';

Then,

GRANT ALL ON *.* TO 'myuser'@'localhost';
GRANT ALL ON *.* TO 'myuser'@'%';

And finally don't forget to flush privileges

FLUSH PRIVILEGES;

Note: If you’ve configured a firewall on your database server, you will also need to open port 3306 MySQL’s default port to allow traffic to MySQL.

Hope this helps ;)