Step 1 – Uninstall MySQL Packages

First, uninstall all the MySQL packages installed on your server. Use one of the followings commands as per your Linux distribution.

sudo yum remove mysql mysql-server    #CentOS and RedHat systems 
sudo apt remove mysql mysql-server    #Ubuntu and Debian systems 
sudo dnf remove mysql mysql-server    #Fedora 22+ systems

Step 2 – Romove MySQL Directory

Now we need to remove MySQL data directory from system which by default exists at /var/lib/mysql. If you didn’t find this, It may be changed to some other place, which you can find in my.cnf file with variable datadir. Delete the /var/lib/mysql directory from the system but we prefer to rename it to keep a backup of existing files.

sudo mv /var/lib/mysql /var/lib/mysql_old_backup
sudo mv /etc/mysql /etc/mysql_old_backup

Step 3 – Install MySQL Packages Again

After removing MySQL completely, install it again using package manager, It will recreate MySQL directory under /var/lib/. Below are the commands to install MySQL from default package repositories.

sudo yum install mysql-server    #CentOS and RedHat systems 
sudo apt install mysql-server    #Ubuntu and Debian systems 
sudo dnf install mysql-server    #Fedora 22+ systems