Consider that there are 100 windows virtual machines coming from a single base image and each vm is added to domain along with minor other machine specific settings which can be done by a script.
After a week say I want to update all vms with a security patch. There are two methods to do this:
Destroy all vms, update base image, create all vms again.
Issue: This requires all the vms to be destroyed, create disk again, define vm, then run required scripts which take care of vm specific configuration with multiple reboot cycles as required.
Manually update all vms and apply the security patch.
Issue: Just cannot scale. May be okay for a set of 5-10 vms not 100s.
I am curious how do other people/softwares do it? Is there a better approach or can I improve my 1st method?