Scheduling automatic updates in yum is  very easy. You can safely enable the auto updates in yum. It can be done  simply by editing the yum updates configuration file. Please go through  the following steps:

# nano /etc/yum/yum-updatesd.conf

Find the below line in the configuration file:

do_update = no

Now, change it to

do_update = yes

Now, save the file and exit. The changes will take effect only after you restart “yum-updatesd”. Enter the following command:

# /etc/init.d/yum-updatesd restart

Once you enter the above command, it will restart and the YUM automatic updates will be successfully enabled on your dedicated server.  You should make sure that your server have all the lastest security  updates and patches. The best way to get informed about the latest  updates and patches is to subscribe the security updates mailing list of  your distribution.


for CentOS 6, please refer below link:

  1. http://samdoran.com/automatic-updates-in-rhel-6-and-cent-os-6/

  2. http://linuxaria.com/pills/enabling-automatic-updates-in-centos-6-and-red-hat-6