How to properly patch vulnerabilities in the clouds on a large number of servers?

Question

System administration

Clouds are being used more and more.
Clouds usually use current virtual images or are created using packer.
As a configuration manager for rolling out to certain application virtual machines, ansible is most often used or nothing is used at all (since everything is configured using packer and terraform).
Let's say a vulnerability like Heartbleed or Shellshock has appeared.
How will you update your virtual machine fleet?

PS I have an option that I think is the most suitable. I'll add it later. I would like to see your ideas.

Answer 1

The only difference from the "old" data center is the relatively short lifetime of the machines.
So, IMHO, the same ansible that builds a list of machines dynamically.