mysql is mysqld, specifically mysql is the application mysqld is the executable name for the service.

The /etc/mysql folder contains configuration files, /var/lib/mysql/ contains the database files, /var/log/mysql/ contains the log files…

And finally /usr/sbin/mysqld which is the actual program, which is started by a service named mysql.service

This file is located in /lib/systemd/system

If systemctl start mysql does not work, you may be missing files, configuration may be incorrect

@richieframe has mapped out the files for you nicely, now to deal with the startup issue.

Try using the command sudo systemctl start mysql to invoke a startup of the MySQL Server.

Should this fail then look for ‘ERROR’ in the mysql error log. This should be found at the path described in your configuration file.

If you get a successful startup it’s worth looking at the log anyway to ensure that there were no peripheral issues with starting MySQL. This is considered best practice.

Good luck,

Andmoo