Have you been in a company with ~2000+ servers where devs install their apps on these OSs and building packages that refuse to upgrade to the latest OS? I mean even with LTS a 20 year old company may still have 3-4 LTS OSs because that last 5% refuse to or cannot upgrade their application to work with the new OS. Sure you could VM the entire thing, but Docker + K8s removes that completely.
> Have you been in a company with ~2000+ servers where devs install their apps on these OSs and building packages that refuse to upgrade to the latest OS
THats what ld_preload is for. But real talk, if you have 2k servers and you can't package your apps to run on your OS, then you need a different platform team.
We managed 36k servers using fucking salt and perl. We were packaging nvidia drivers and all sorts. One system that everyone used still needed the athena widget set.
But the main point is, if you're using old packages, then you're gonna get hacked. You either need to kill that app, fire that developer or virtualise it and fill out the risk register, and do monthly recovery tests.
Docker allows you to pack in CVEs like no tomorrow. so sure k8s can let you do that, and given the hardly anyone properly enforces namespace isolation, so they can have a service mesh, you can still steal loads of data from a compromised container.
If developers don't maintain their apps, it doesn't really matter that much how and where you deploy them. With Kubernetes, you just end up with unmaintained Docker images that potentially contain a ton of vulnerabilities.
But with a containerized app image you can reduce the blast radius of the poorly maintained app compared to running it bare metal on a host with other services. Also you can still maintain base images to patch/try to reduce vulnerability surfaces
Have you been in a company with ~2000+ servers where devs install their apps on these OSs and building packages that refuse to upgrade to the latest OS? I mean even with LTS a 20 year old company may still have 3-4 LTS OSs because that last 5% refuse to or cannot upgrade their application to work with the new OS. Sure you could VM the entire thing, but Docker + K8s removes that completely.