Centos Cheat Sheet
https://www.shiftescape.com/2021/12/how-to-lamp-on-centos-7-with-phpmyadmin.html
https://www.shiftescape.com/2021/12/how-to-cron-job-in-centos-78.html
https://linuxhint.com/screen-command-centos/
Listing process on port
$ netstat -ltnp | grep -w ':80'
List all processes
# ps -A
for finding pid of particular process
# pidof mysqld
to kill a process
kill -9 3139