Then a developer deploys their "loose files" on top a couple of times, so now you have the image plus god-knows-what.
The VM scale set scales out.
What version of the app is running on which instance?
Answer: Mixed versions.
Rsync is smart enought to figure out how to get parity.
>What version of the app is running on which instance?
There is always going to be a time during a rollout where there are mixed versions running.
Nobody expects a month old version to occasionally turn up and then mysteriously disappear when some rsync job catches up.
