Principal Skinner on Immutable Distros
cross-posted from: https://infosec.pub/post/15781466
Am I out of touch?
No, it's the forward-thinking generation of software engineers that want elegant, reliable, declarative systems that are wrong.
But an immutable distro is not necessarily declarative, and the other way around.
Why lump them together?
an immutable distro is not necessarily declarative
It is necessarily so. You can't configure an immutable distro by a sequence of mutations.
But yes, the other way around is quite possible.
You can't configure an immutable distro by a sequence of mutations.
Isn't that literally how ostree works?
NixOS isn't immutable though. It runs on normal writable ext4 by default.
Immutable was adopted for Android because Google and the Android vendors wanted to lock down the platform, and because they always distribute their OS images and updates as binary blobs.
It offers no benefits to an open ecosystem like Linux, that you can't already accomplish with existing security measures.
It offers some benefits to distro maintainers who are only willing/able to focus on the core system and delegate the rest of the software to distro-agnostic packages. That's definitely an interesting niche and I look forward to it. But please note that whether the core is immutable is completely irrelevant in this scenario.
Generally speaking, if you want to use distro-agnostic packages you can do that regardless of whether the system is immutable or not.
And since we're on the topic, if we're borrowing things from Android I would love to have the application sandboxing and permissions. I think they'd be a much bigger benefit โ to all distros, immutable or not.
Immutable partitions are amazing for reliability, then you can just OverlayFS your mutable state on top of it
The problem with making the core immutable is that you have to decide where you draw the line between immutable and regular packages.
It sounds nice to be able to always have an immutable blob with some built-in functionality that you can fall back to, but the question is how far do you want to take that blob?
Things that go into the immutable blob don't offer much (if any) choice to the user. I can see it being used for something like the kernel and basic drivers, coreutils, basic networking. It starts getting blurry when you get to things like systemd and over-reaching when it gets to desktop functionality.
Also, you say it's more reliable but you can get bugs in anything. Version x.y.z of the kernel can have bugs whether it's distributed as part of an immutable core or as a package.
I definitely think distributing software as immutable bulk layers can be useful for certain device classes such as embedded, mobile, gaming etc. The Steam Deck for example and other devices where the vendor can predefine the partition table and just image it with a single binary blob.
On the desktop however I struggle to see what problems immutable solves that are not already solved some other way. Desktop machines require some degree of flexibility.
And since we're on the topic, if we're borrowing things from Android I would love to have the application sandboxing and permissions. I think they'd be a much bigger benefit โ to all distros, immutable or not.
Flatpaks and Wayland should fill out this part nicely.
This often means unofficial builds that aren't from the developer that sometimes have sandbox specific issues the devs didn't contemplate because they don't actually do flatpaks. If someday the random bob who is neither the original developer nor some trusted individual connected to the distro is hacked they may push out a malware enabled update that pwns all the people who automatically update in short order. This doesn't seem like a security increasing feature.
I donโt think anyone uses immutable distros for security, the main selling point I believe is that you can rollback when the system breaks due to a update, especially when itโs a rolling release
I can do that with Timeshift on any distro
Look, if you love declarative systems that's cool. I'm genuinely happy for you that you have much better options now. That can only be good.
That being said, they only solve problems that I don't have. I do not care even the tiniest amount about whether a system is declarative or not, and I'm definitely not going to go out of my way to seek them out. If you want to call that "out of touch" then so be it.
I just like them because my system feels โcleaner.โ Always drove me nuts with Arch or Debian when you install something, letโs say it requires ~20 decencies, then you remove it later, run the respective dependency clean command, and it only removes lets say ~12 packages. Like where did those 8 dependencies go? Are they just stuck on my system forever? Atomic desktops donโt have this issue which I really appreciate.
The 8 dependencies must be an optional dependency for some other package you already have installed. That said, that kind of stuff is the main reason I want to try NixOS - any time I install something, configure something, etc. I'm risking forgetting about it and getting tripped up over it down the line, with no good way to check.
I want this but without learning a new functional language to do it.
Just waiting for one that requires you to compile one Monad to define your whole distro. Types all the way.
Then I'm writing a blog post how your Linux distro is a burrito.
ostree go brrrr
Aeon is the way
Imagine being so devoid of soul and spirit you turn your OS into kubernetes
Not sold on declarative systems in all domains. It often creates unnecessary complexity for little advantage.
Immutable root has huge benefits in large deployments for consumers, enterprise or servers. Really great for Chromebooks and consoles. Probably would benefit the majority of Windows installations, certainly in enterprise. I do not like the idea of critical systems being updated with random shit becoming standard practice as in WIndows/Clownstrike land. Those guys have normalised insanity to the point they think we are the crazy ones.
However I like to mutate my desktop and development systems. I use linux because I like the freedom to tinker and that includes the freedom to mess stuff up. In practice having root writable only by a privileged user, a signed software distribution and knowing what I am doing mostly keeps me out of trouble. On the very rare occasions I find myself without a bootable system (it has happened to me more than once in 30 years) I know how to recover and it doesn't stress me.
Oh I definitely am out of touch, but I think I'll live with that ๐
Eh, bring it all on. Part of what is great about FOSS is the vibrant ecosystem. I welcome new stuff, even if I don't have much use for it.
I do think it makes a lot of sense for certain use cases. Like my Steam Deck, great use case for an immutable distro.
Another is school or work deployments where you just need a herd of identical, generic systems or thin clients that run the same small set of applications.
Hehe, but unix shell scripting can do so much...
I just treat my systems like cattle not pets. Get out of line and I will kill ya and bring a fresh copy online
Is there any declarative OS that is not immutable?
I tried Fedora Silverblue once and it was all fun and games until I wanted to build a driver.
But I really like the concept of declarative systems.
What's the best immutable OS?
NixOS
Immutable and Declarative OS design is simply an option. I think it's a damn good one, but right now, it's not for me. That could easily change in the near future.
The idea excites me. A potential hardened OS that user-friendly could be a great option for Business and Academic computing.