[CentOS] Upgrade security relevant packages

Hello,

I'm looking for a solution to automatically yum update security relevant packages on a couple hundred Centos6/7 servers. The deployment/trigger would be Ansible.

I looked into the "yum-plugin-security" and tested it on a CentOS 6 installation but always found no security relevant updates (yum list-security/yum --security update) where there should be at least a couple ones. I read around it and found that this solution is not working for CentOS (can you please confirm). What is the best practice to upgrade security relevant packages on live systems without service interruption?

Thanks in advance!

Cheers,

Chris