I’ve been messing around with Docker recently, and I stumbled upon this intriguing question that I can’t quite shake off. So, picture this: I’ve got this Docker container that’s been running Ubuntu 18.04 for a while now. It’s been doing its job, but I keep hearing good things about Ubuntu 20.04 and all the new features and improvements it brings. Naturally, I want to upgrade it, right? But I can’t help but wonder if it’s really feasible to just upgrade the container instead of starting from scratch.

I mean, ideally, I would love an easy upgrade path, like running a simple command inside the container that handles everything — or is that just wishful thinking? I’ve read some online debates where folks seem divided on the topic. Some say that upgrading an OS within a Docker container isn’t the best practice, primarily because of how Docker images are built and how they tend to favor reproducibility. You know, the whole idea that each container should be a self-contained package that doesn’t rely on the underlying host system to function properly.

But then again, others argue that you can just update it in place. They mention doing a typical upgrade process like you would on a regular system using commands like `do-release-upgrade`, and that it should generally work fine if you have the right dependencies sorted out. But what about potential issues? What if things break and the container becomes unstable? Or worse, what if I lose all the configurations and data I set up within the container?

Honestly, I’m kind of torn. If it’s possible, I’d love to hear how others have fared with upgrading in place versus creating a new image from scratch. How did you go about it? Did you hit any snags along the way, or did it go off without a hitch? Also, what are the pros and cons you’ve noticed in either approach? Any tips or lessons learned would be super helpful! Let’s get this discussion rolling!