Day 9 - MariaDB Troubleshooting
https://github.com/imShakil/100-Days-Of-DevOps-Challenge-KodeKloud/blob/f9be26cdcfafab77059be98cfc4e630749719f74/days/009.md?plain=1 ---- is not helpful.
I don’t find the file - cat /etc/my.cnf.d/mariadb.service - how to fix it.?
It wouldn’t be in /etc/my.cnf.d: that’s the location of mysql settings. mysql.service is systemd service file. You’d expect it to be somewhere like /usr/lib/systemd/system/mariadb.service, which the page you’re referencing also mentions 
Look at systemctl status mysql which will tell you where the service file is.