Free Internet Online Database

 Edit MySQL config file
 Configure firewall
 Connect to remote MySQL server

Step 1: Edit MySQL Config File

1.1 Access mysqld.cnf File

Use your preferred text editor to open the mysqld.cnf file. This example uses the nano text editor in Ubuntu 18.04. Enter the following command in your command-line interface to access the MySQL server configuration file:

The location of the file may vary based on the distribution and version in use. If the MySQL configuration file is not it its default location try using the Linux find command to detect it.

1.2 Change Bind-Address IP

You now have access to the MySQL server configuration file. Scroll down to the bind-address line and change the IP address. The current default IP is set to 127.0.0.1. This IP limits MySQL connections to the local machine.
The new IP should match the address of the machine that needs to access the MySQL server remotely. For example, if you bind MySQL to 0.0.0.0, then any machine that reaches the MySQL server can also connect with it. For this website to access it you need to use IP address 212.47.237.65
Once you make the necessary changes, save and exit the configuration file.

Note: Remote access is additionally verified by using the correct credentials and user parameters you have defined for your MySQL users.

1.3 Restart MySQL Service

Apply the changes made to the MySQL config file by restarting the MySQL service:

Next, your current firewall settings need to be adjusted to allow traffic to the default MySQL port.

Step 2: Set up Firewall to Allow Remote MySQL Connection

While editing the configuration file, you probably observed that the default MySQL port is 3306. This is default MySQL port number but can be changed in the config file.

If you have already configured a firewall on your MySQL server, you need to open traffic for this specific port. Follow the instructions below that correspond to your firewall service in use.

Option 1: UFW (Uncomplicated Firewall)

UFW is the default firewall tool in Ubuntu. In a terminal window, type the following command, changing remote_ip_address to the required IP address, to allow traffic top the IP and port:

The system confirms that the rules were successfully updated. Firewall rule added to firewall deamon.

Option 2: FirewallD

The firewalld management tool in CentOS uses zones to dictate what traffic is to be allowed.
Create a new zone to set the rules for the MySQL server traffic. The name of the zone in our example is mysqlrule, and we used the IP address from our previous example 212.47.237.65:

sudo firewall-cmd --new-zone=mysqlrule --permanent
sudo firewall-cmd --reload
sudo firewall-cmd --permanent --zone=mysqlrule --add-source=212.47.237.65
sudo firewall-cmd --permanent --zone=mysqlrule --add-port=3306/tcp
sudo firewall-cmd --reload

You have successfully opened port 3306 on your firewall.

Option 3: Open Port 3306 with iptables

The iptables utility is available on most Linux distributions by default. Type the following command to open MySQL port 3306 to unrestricted traffic:

To limit access to a specific IP address, use the following command instead:

This command grants access to 212.47.237.65. You would need to substitute it with the IP for your remote connection.
It is necessary to save the changes made to the iptables rules. In an Ubuntu-based distribution type the following commands:

sudo netfilter-persistent save
sudo netfilter-persistent reload

Type the ensuing command to save the new iptables rules in CentOS:

Step 3: Connect to Remote MySQL Server

Your remote server is now ready to accept connections. You can now use this site to connect to your MySQL databases, using your server IP, username and password.

How to Grant Remote Access to New MySQL Database?

If you do not have any databases yet, you can easily create a database by typing the following command in your MySQL shell:

To grant remote user access to a specific database:

The name of the database, the username, remote IP, and password need to match the information you want to use for the remote connection.

How to Grant Remote Access to Existing MySQL Database

Granting remote access to a user for an existing database requires a set of two commands:

update db set Host=’212.47.237.65' where Db='yourDB';
update user set Host=’212.47.237.65' where user='user1';

User1 is now able to access yourDB from a remote location identified by the IP 212.47.237.65.

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