I recently started working with RightScale to manage servers in various cloud environments. The servers that I am working with are in the Amazon EC2 cloud, but RightScale provides an interface to manages servers in multiple cloud spaces.

The underlying operating system for the servers that I am managing are running CentOS. While I prefer RedHat, CentOS is fine. I understand the reason for going with both, and when cost is an issue CentOS commonly wins out. The version is CentOS version 5.4.

The problem is that the servers are not getting updates. Based on the RightScale blog, you should be able to choose a RightScale supported frozen image of the CentOS mirrors from any given day, and they will have the most up to date patches to that day. As the servers do not maintain state between reboots, this means you can set the repo for a specific date, and the patches would be consistent for multiple machines no matter when they were booted.