How to use yum-cron to automatically update RHEL/CentOS Linux

Originally published at: https://www.cyberciti.biz/faq/fedora-automatic-update-retrieval-installation-with-cron/

The yum command line tool is used to install and update software packages under RHEL / CentOS Linux server. I know how to apply updates using yum update command line, but I would like to use cron to update packages where appropriate manually. How do I configure yum to install software patches/updates automatically with cron?