How to Change the Default Database Port Number for MySQL/MariaDB

When managing a MySQL or MariaDB database, it's sometimes necessary to change the default port number to ensure compatibility with other applications or to improve security. In this guide, we'll walk you through the steps involved in changing the default port number for your MySQL/MariaDB database server.

Why Change the Default Port Number?

Changing the default port number can be beneficial in several scenarios:

* Compatibility: If you're using multiple applications that rely on different port numbers, changing the default port number can help resolve conflicts and ensure smooth operation.

* Security: Changing the default port number can make it more difficult for hackers to identify your database server, thereby improving security.

Step-by-Step Instructions

To change the default MySQL/MariaDB port number in Linux, follow these steps:

1. Edit the MySQL Server Configuration File: Open the MySQL server configuration file in a text editor using the command `sudo nano /etc/my.cnf` (for CentOS 7) or `sudo nano /etc/mysql/my.cnf` (for Debian-based distributions). Locate the `'mysqld'` section and add the following line: `port = `.

2. Restart the Database Daemon: After making changes to the configuration file, restart the database daemon by issuing the command `sudo systemctl restart mysqld` (for CentOS 7) or `sudo service mysql restart` (for Debian-based distributions).

3. Update Firewall Rules: Once you've changed the MySQL/MariaDB port number, update your distribution's firewall rules to allow incoming connections to the new TCP port.

4. Verify the New Port Number: You can verify the new MySQL port by logging in to the database server with the root account and issuing the command `SHOW VARIABLES LIKE 'port';`. Alternatively, you can use the `netstat` or `ss` command to display information about open network connections.

Additional Tips

* When changing the default port number, ensure that all applications and services relying on your MySQL/MariaDB database are updated to use the new port number.

* If you're using SELinux, you may need to add a custom rule to allow the database server to bind to the new port. You can do this by issuing the command `semanage port -a -t mysqld_port_t -p tcp `.

* Remember that all connections to MySQL on localhost are made via the MySQL unix domain socket, not via the TCP socket.

By following these steps and tips, you should be able to successfully change the default port number for your MySQL/MariaDB database server in Linux.

Mysql port number