I'm planning on setting up a new server using kvm. On the host and almost all the vm's I want to use Debian or CentOS. But there came an interesting question to my mind. Since kvm can be scaled up a lot, what is the best way to keep all the guests up-to-date and on the same "up-to-date-level" without running the update manually? Lets assume we are talking about 100 guests, each running a different service. My thought ended with the idea of a own repo, that all guests will automatically update from. You maybe don't want all software updates from the official repos to be installed. Is there any other good way to achieve this? Maybe by using some kind of management software or something?
You can use a local repository and a configuration manager software installed on bare metal or excluded by the pool of managed system. There are many configuration manager software, two examples:
- HP server automation
When you want upgrade a group of system, you need to modify the configuration of the "configuration manager software" and the upgrade process is executed automatically.
If you are using Centos, SpaceWalk is the way to go - http://wiki.centos.org/HowTos/PackageManagement/Spacewalk