NixOS is a good server OS, except when it isn't

https://sidhion.com/blog/posts/nixos_server_issues/

by IrisBMeredith • 2 years ago

182 168 2 years ago

Good stuff! From the title I thought this would be about sysadmin woes, but this is interesting too :)

Another little addendum: you can trivially create bootable custom NixOS installer images with whatever configuration you want pre-applied[0].

[0] https://nix.dev/tutorials/nixos/building-bootable-iso-image

rendaw3• 2 years ago

You can just use them as immutable live systems too, with the unfortunate requirement that it'll call your system an installer: https://github.com/NixOS/nixpkgs/issues/338738

evgpbfhnr2• 2 years ago

Couple of things spring to mind:

- didn't check if nixos uses it, but coreutil has a single binary mode (like busybox, a single binary is built and symlinks or hardlinks are used to provide all the commands); that might save some space

- instead of trying to strip down the system, maybe go the other way around: only include the command you need with its closure? closure computation is done in a few places (apparmor profile or systemd.confinement come to mind) and it should be possible to just copy whatever your server binary needs, your kernel (since microVM and not container), and run the binary directly as init (maybe with a simple wrapper that hardcodes network or whatsnot)

good luck!

pxc3• 2 years ago

- didn't check if nixos uses it, but coreutil has a single binary mode (like busybox, a single binary is built and symlinks or hardlinks are used to provide all the commands); that might save some space

It does. If you have coreutils from Nixpkgs installed you can check this with

  basename "$(realpath "$(which ls)")"

If you see 'ls', you're looking at separate binaries. If you see 'coreutils', it's a symlink to a singular 'coreutils' binary.

yjftsjthsd-h2• 2 years ago

go the other way around

I'm not sure about just the one closure since the result needs to boot, but more generally that looks reasonable if your use case fits. There's a couple efforts, IIRC, mostly centered around router firmware where "real" nixos doesn't fit, ex. https://gti.telent.net/dan/liminix

hamandcheese8• 2 years ago

2 is very interesting to me. I'd love to see an example of a "scratch" vm build, in a similar spirit to scratch docker builds. Assume I have all my software and kernel built, what is the minimal filesystem that will boot? How much easier can it get when I am only targeting a VM?

rkeene2• 2 years ago

This might be something you're interested in: https://appfs.rkeene.org/web/dir?ci=trunk&name=build/qemu

It's for running AppFS inside a VM on QEMU. It uses a statically linked Tcl (which AppFS is written in) to bring the system up.

microtonal• 2 years ago

The post is much more interesting than the title suggests. Great deep dive into slimming a NixOS system.

koito17• 2 years ago

I agree. The title made me expect a low-quality, clickbait article. The actual article provides a lot of educational value to users of Nix and those interested in trying to build the smallest Linux distribution that can run Nix. Despite using Nix (the package manager) for so long, I haven't considered what it would take to get this. The article answers the question perfectly.

yjftsjthsd-h2• 2 years ago

Disk space is why one of my laptops doesn't run NixOS; 16GB soldered storage fit one generation passably, but it was clear that it wasn't gonna work (of course, that's with X and a browser; totally different use case). I vaguely recall that locales were shockingly large and I couldn't figure out how to trim them down. So that box runs Alpine now, which easily fits with no effort.

shim__• 2 years ago

Have you tried putting /nix on an filesystem with compression? I've experienced >50% in storage savings with Bcachefs + zstd and dedupe

GianFabien• 2 years ago

I too use Alpine. I like how you start small and add what you need. The option of having a read-only root FS is convenient on flaky SBCs.

SuperSandro20009• 2 years ago

The locale default seeing has been fixed by me over a year ago but 16GB is pretty small to fit two systems which you need to switch.

Larrikin• 2 years ago

Have there been any good efforts into getting rid of the language or providing an alternative? My effort into switching and the biggest complaint I've read is that the idea behind NixOS and the ecosystem is genius but one of the biggest draw backs is writing everything in Nix.

I spend a weekend every so often defining the core of what I want next time I upgrade, but just find it so annoying I'm sure I won't use anything I've written until there's a major change in the ecosystem.

maxloh• 2 years ago

It seems to be an issue with testing and debugging, rather than the language itself. The same issue would also be present if you could switch to any other language for configuration.

kjuulh• 2 years ago

Nickel lang is such an effort. Id say the syntax is a mix of json and lua and aims for a non-touring complete program. It is still a bit early but it looks promising

pxc3• 2 years ago

No, Nickel is Turing-complete. That's been one of the characteristics intended to distinguish it from most other configuration languages from the start.

See the 'RATIONALE' document: https://github.com/tweag/nickel/blob/378ece30b3e3c0ab488f659...

turboponyy2• 2 years ago

What's so bad about it?

Putting aside the poor typing (the lack of proper typing is a shame, so valid criticism), I actually really like the language - it's genuinely a great DSL for the particular problems it's supposed to handle.

It does take a bit of use for it to click, though. A lot of it has to do not with Nixlang itself but about learning nixpkgs' idioms.

k_bx2• 2 years ago

It's not just poor typing. It's the lack of discoverability. "What are all my options here in this expression? What are the symbols available?"

I think a good IDE integration could solve this, but not sure how much is possible.

logicchains• 2 years ago

Way too much sugar/"idioms", which makes it hard for someone new to the language to figure out what a given piece of code is actually doing. Confusing use of semicolons for what almost every other language uses commas or newlines (or nothing) for. It's the same feeling as writing bash, and needing to always look up again exactly what the syntax is and where the semicolons go.

adrian_b• 2 years ago

There is Guix, which replaces the Nix language with Scheme, but which has some limitations related to a smaller user base, e.g. a smaller package collection.

Replacing the language requires duplicating all the work that went into Nix, to reach parity, so it is not easy.

duped3• 2 years ago

Replacing the language requires duplicating all the work that went into Nix, to reach parity, so it is not easy.

That seems like a design flaw in Nix, there's no reason the data model should be so tightly coupled to the scripting implementation that you can't reuse packages written in a different language.

kkfx4• 2 years ago

The biggest limitation IMO it's that they are HPC-centric, not caring the desktop, which is the was to allow more people discovering a distro. Also the lack of a proper zfs and lvm/mdraid/luks support it's a big showstopper.

poincaredisk3• 2 years ago

IIRC guix started off by being compatible with nix package derivations, but they broken it (i also may remember incorrectly).

If nothing changed, they also have a strong ideological drive and funny support any non-free software.

SuperSandro20009• 2 years ago

Scheme is so much worse. It has so much repetition and is so much more verbose for no reason.

umanwizard3• 2 years ago

Have there been any good efforts into getting rid of the language or providing an alternative?

Guix is conceptually similar to Nix but uses scheme.

tkz13125• 2 years ago

I find the nix language to be quite pleasant. There are some syntax quirks and types would be nice, but in general the “json with functions” vibe is imo great and a very nice fit for the domain. Lots of other modern config languages (e.g. dhall, jsonnet) have ended up in this part of the design space too.

With that said tweag has been working on a kind of nix 2.0 / nix with types for a while with the aim (I think) of being able to use it in nixpkgs: https://github.com/tweag/nickel

the_duke• 2 years ago

I also quite like nixlang for config tasks - in theory! In practice its really annoying. I think the main problem is the interpreter and the bad error messages / bad debuggability.

Part of that just comes from lazy evaluation, which makes debugging a lot harder in general (you feel this in Haskell...), but also just from nix not being a big popular language that gets lots of polish, and being completely dynamically typed.

poincaredisk3• 2 years ago

Nix is ok. I like jsonnet more, and once I've tried to write a converter from jsonnet to nix, but it turned out this is much harder than expected (some idioms don't transfer from nix to jsonnet well.

anon2919• 2 years ago

Me as well. As a haskell / ML programmer, it is extremely intuitive. It's non-innovative (In a good way). Literally it's just a functional scripting language.

seanhunter• 2 years ago

I don't think the language is the issue here[1].

It seems inevitable to me that some of the design choices around immutability and isolation are going to result in a larger server image (both on disk and in memory) than if you are prepared to forgo those things. For most people that tradeoff is probably worth it but if you want something to run in an embedded server or with a very low disk footprint it's probably not right for you.

Around 20 years ago people who wanted to do this[2] used to make tiny immutable redhat servers by remounting /usr and a few other things read-only after boot so it's certainly doable but it's a lot more of a pain than what nix does and there is no process isolation and no rollback etc when things go wrong.

[1] ...or generally in fact but that's a matter of opinion and I know people feel differently about this.

[2] me for one, but others also.

SuperSandro20009• 2 years ago

What do you want to replace it with? YAML?

The language won't go away and you should try to look at it for more than I don't like it.

frankjr• 2 years ago

The Nix language also doesn't need to exist. They want to write pure lazy declarative derivations - great, you can do that in any existing language. It's a matter of style and APIs. You don't need to spend years developing a brand new language from scratch. Not to mention that many derivations end up calling a Bash script underneath anyway because at some point you actually need to perform an action in the real world. How would a derivation looked like if written in <insert your favorite scripting language> with lazy APIs?

weatherlight• 2 years ago

That's not true. The language needs to be declarative. if you use your favorite lang and develop a DSL around those APIS, that DSL would be declarative.. also the language itself, isn't that complicated.... it's really quite minimal. It has its roots in ML. I honestly think people expect everything to look like javascript or C++ and it's a shame honestly.

packetlost• 2 years ago

The Nix language is basically what you'd get if you were designing a DSL for declarative configuration of extremely deeply nested trees. Nearly every "feature" in the language is for making that easier. You could probably write a Nix -> JSON compiler and end up with something completely unreadable because the language hides so much of what's actually present in the fully resolved tree.

anon2919• 2 years ago

Meh... the nix language being as it is makes it a lot easier to write these things with less cruft. Every attempt I've seen at introducing laziness into a language like python, c++, rust, javascript, etc just seems to require a lot more unnecessary keywords and helper functions and cruft.

otabdeveloper4• 2 years ago

No, writing this in any other language will definitely make for a much shittier Nix experience.

The problem isn't the language, the problem is that nixpkgs (and NixOS) are just huge.

Nathanba• 2 years ago

yes, https://github.com/garnix-io/garn But weirdly there was little interest and they rebranded themselves around being a more general build system based on nix instead of what they originally said about being a nix reimplmentation in typescript.

mipselaer• 2 years ago

Could you run ’nix store optimise’ before you remove ’nix’?

pxc3• 2 years ago

I was trying to bring NixOS to a bare minimum, which is an exercise similar to building containers with the bare minimum required for the software in the container to run. I think this is a worthy endeavour. I think we have all the tools in regular non-docker, non-kubernetes linux to get to a similar outcome, except we won’t need docker or kubernetes or whatever in this new land, thus removing quite a bunch of complexity from the systems we build.
But doing it on top of NixOS currently feels like a bad path to take.

The author of this blog post might be interested in playing with not-os, another, much smaller OS built with Nix: https://github.com/cleverca22/not-os

Could be a decent source of inspiration!

niz4ts3• 2 years ago

(I'm the post author)

Thanks! I have to admit that I've had the itch to build my own NixOS-inspired system more than once, and I haven't done that because I just don't have time to dedicate to this among all the other projects I'm working on. I wasn't aware of not-os before, but I'll definitely dig into the code!

0x1ceb00da3• 2 years ago

He didn't mention that nix uses a lot of ram. If your server is tiny and doesn't have swap enabled, running nix command s will make it unresponsive. Are there any nixos alternative that allow you to do system wide configuration from a single source similar to configuration.nix?

clhodapp• 2 years ago

It won't necessarily do that if you deploy to your server from a remote machine over ssh

dlahoda• 2 years ago

author does not use nix on his nixos and removed it, so no ram issue.

author does not activate new config on host machine, but deploys new host machines as needed.

he evals on build/dev/ci machine only.

hamandcheese8• 2 years ago

You need not perform your nix evaluation on the same device you are targeting. You can nix copy a system closure to your target and activate it, and there are a number of tools in the nix ecosystem to make this easier.

Granted, if you local machine is low on RAM, or isn't Linux, then you will be in trouble.

TheDong• 2 years ago

If you have a different machine with more ram and compute, you can use 'nixos-rebuild --target-host=<server> switch'. That does all the nix building on the local machine, and then just copies binaries and activates the built configuration on the remote machine.

0x1ceb00da3• 2 years ago

I don't run nixos on my PC

niz4ts3• 2 years ago

(I'm the post author)

As others said, I've moved away from doing nix builds on servers and into a less wasteful (if you're running multiple servers) approach of building once, deploying the bits into a cache, and making the servers fetch them from a cache. I've been slowly working on my own tool to make this workflow easier (nixless-agent, you can find an early version on GitHub).

jmholla• 2 years ago

Do you have a post on your setup? I'm relatively new to NixOS server management and I've been leaning on NixOps for the coordination bits. I'd love to see what you're doing as it sounds more elegant, efficient, and supported.

prmoustache2• 2 years ago

I haven't tried it personnally but Guix is similar with config in guile scheme. Have a look at the documentation [1][2].

Caveat: it is a gnu project so no proprietary stuff like firmwares and drivers included out of the box (but there is a community guix nonfree project available [3]). I believe that isn't a problem for virtual machine servers anyway.

[1] guix cookbook: https://guix.gnu.org/cookbook/en/html_node/index.html#Top

[3] guix manual: https://guix.gnu.org/manual/en/html_node/index.html#Top

[3] https://github.com/guix-users/guix-nonfree

umanwizard3• 2 years ago

The widely used nonfree guided channel is https://gitlab.com/nonguix/nonguix, not the one you linked.

lugu• 2 years ago

Not similar to nix, but you can look into Yocto. You can use it to generate an OS. It is, much more involved than using nix, but suitable for low memory environments.

bayindirh• 2 years ago

Yocto is also used by Lenovo to build their software appliances like XClarity Administrator.

Also it’s very famous and loved in embedded software circles.

tombl• 2 years ago

The problem with nix is that compiling a system uses lots of memory, but when deployed there's little overhead.

Like you would with Yocto, I just build my systems on a proper host then remotely deploy them.

exe34• 2 years ago

guix?

0x1ceb00da3• 2 years ago

Doesn't it use nixos underneath?

anon2919• 2 years ago

The best thing about NixOS is that it's extremely easy to replace systems. On my infrastructure, I have a centralized server where I store all my nix artifacts in /nix/store.

Then on boot for my other systems, they boot into a minimalist nixos image (via netboot) that (1) lookups up the hostname assigned to the system, (2) uses `nix copy` to move the closure of the current system from the main host where I store my builds to the local one, (3) switches into the system (explained below), and (4) then uses nixos's kexec support to switch into the proper kernel booting into the new system.

How to switch into a system: every nixos closure has a top level `bin/switch-to-configuration` script that nixos-rebuild suse. Just run `/nix/store/my-hash/bin/switch-to-configuration switch` and your system will silently be replaced by the new NixOS configuration. Very easy!

eptcyka• 2 years ago

This is highly relevant for me, will probably end up using some of the same tricks they've done to trim the size of some of my micro VMs.

johnklos• 2 years ago

Taking the time to delve in to things like this can teach you more about the OS you run than many other things can. It's not too unlike making a crunchgen OS, or even just a read-only OS with overlays. It's sometimes quite enlightening to see what will work with much less than we assumed it needs.

Having just installed the entirety of NetBSD on an i386 system (a 200 MHz Pentium), I see it weighs in at around 1 gig. But that's everything including X11 with WM and the toolchain (gcc 10). That's not bad, but it's really amazing how much of that isn't necessary for running the OS on a server. Particularly where you might want tiny VM images

hamandcheese8• 2 years ago

One technique employed by microvm.nix[0] is to mount the hosts /nix/store into the guest. This won't shrink the size of the system, but should allow it to be amortized across many different VMs.

I'm not sure how exploitable a read-only virtiofs share is, so this is perhaps not appropriate in some circumstances.

[0] https://github.com/astro/microvm.nix

ahachete• 2 years ago

I was thinking of a similar approach, but mounting /nix/store from the host into the guest will only work if you have a single guest.

For multiple guests, you should rely instead on: * A snapshot-able filesystem with the option to create clones (like ZFS). I think this is a great idea actually. * Exporting /nix/store via NFS, so you can have multiple writers (but this creates some tight coupling in that accidentally deleting stuff there may disrupt all guests).

evgpbfhnr2• 2 years ago

mounting /nix/store from the host into the guest works with as many guests as you like - this is what the nixos tests framework does all the time, you just need a different "system" derivation for each (different) VM.

The problem with that is that the VM can see all the needless software, so if your goal is isolation, having a smaller closure is much better from a security point of view: if there's no coreutils bash etc then there's no risk of getting a shell spawned by an attack...

astro1• 2 years ago

If you don't setup the mount, microvm.nix will create an erofs/squashfs image for /nix/store.

goodpoint4• 2 years ago

Any OS without stable releases and a security team is not a server OS.

ladyanita22• 2 years ago

Then you only have Ubuntu, Fedora, Red Hat/CentOS/Alma/Rocky and Suse/OpenSuse.

goodpoint4• 2 years ago

and Debian.

bpye• 2 years ago

NixOS does have "stable" releases every 6 months, but they don't have long term support.

goodpoint4• 2 years ago

I mean stable without quotes, or LTS if you prefer :)

NixOS gives you a month of time to move to a new release. Most LTS distros 5 to 10 years.

Diti2• 2 years ago

https://status.nixos.org/ https://nixos.org/community/teams/security/

Welcome to NixOS, then! :)

goodpoint4• 2 years ago

yeah, not quite...

SuperSandro20009• 2 years ago

You mean rot and forget LTS?

kstenerud8• 2 years ago

I just finished moving all of my servers off NixOS and I'm finally breathing a sigh of relief.

Deterministic systems are a cool idea, but we're just not there yet. The headaches and pain involved in maintaining these systems and warping the software to obey are too great.

Everything in NixOS works, until it doesn't. And when it doesn't, woe be unto you.

judofyr• 2 years ago

What did you replace it with? I've been been using NixOS for a (non-critical) server which replaces another server that was "managed" by Ansible. Now that's it running nicely on NixOS, and while it's far from perfect, I'm really struggling to see how I would manage it in any other way. The experience is so much nicer now.

hamandcheese8• 2 years ago

I'll echo this. I can't imaging going back.

And yes, I have put a lot of blood sweat and tears into making things work in nix/NixOS. The thing that keeps me invested is once I get something working, it is far easier to keep it working. If nixpkgs updates break my things, I'm one git bisect away from figuring out what happened.

kstenerud8• 2 years ago

I use Proxmox on top of Debian. Surprisingly, I'm back to Bash scripts to set things up (because Ansible wouldn't allow me to orchestrate between a host and a guest - so if I have to change container config during setup, I'm back to scripts again, AND the complications of Ansible).

I basically build up Proxmox container templates, and then build upon those similar to how Docker does it (I don't use Docker because they don't allow you to specify your MAC address, so you can't control them from a separate LAN-based DHCP server - instead you have to map a bunch of ports on your host and then configure all external clients to match... so dumb).

I've basically gone full circle at this point:

- Docker

- LXD with Bash scripts

- LXD with a ton of Python

- NixOS

- Proxmox with Ansible

- Proxmox with Bash scripts (albeit much simpler and flatter than last time)

Everything is containerized and has its own IP address on the physical LAN, the templates can be regenerated with a simple script, important data is mapped to a host directory (/home/data/my-container, which gets backed up), and destroying and rebuilding an instance container is a cinch.

One really nice feature of this setup is that I can tear down and rebuild a template, launch a test container from that, copy the instance data in /home/data to the new container, make sure it works with the new stuff, and then launch it for real.

Now it doesn't matter what technology (container or VM) I use. Everything is a completely separate machine as far as the LAN is concerned, which greatly simplifies things.

Everything, from host to software to containers & VMs is built "deterministically" (i.e. deterministically enough) from the scripts. Rebuilding the whole thing (server and all) from scratch takes about an hour and a half. I just use the same set of scripts on all of my servers to make management easier. Hosts have minimal software and configuration, and guests do all the real work. Migrating is an rsync /home/data away.

nextaccountic• 2 years ago

What didn't work in your NixOS servers?

SuperSandro20009• 2 years ago

Same experience with Debian. Preaching religious, unquestionable stability but a soon as you install an out of tree software, everything falls apart in your hands. Any Debian system I used fell apart on upgrades in some unrecoverable way and it was a giant pain in the ass.

The last NixOS stable release I deployed in ~3 hours onto ~30 VMs with only minor issues and everything continued to just work.

kstenerud8• 2 years ago

I don't actually care about uncommon software stability on Debian. The hypervisor is Debian, so it runs very basic happy path software that always gets tested by the Debian team (and/or Proxmox team) for upgrade problems, and then all of my crazy-ass software runs in containers/VMs which are simple to destroy/rebuild if necessary.

The Proxmox team ensures that the hypervisor stuff works, and now I don't have to worry about a basic change to a nix file resulting in "Unknown entity flibblefrazzle" coming from some random place 18 levels deep in the bowels of the package system/os. It really got to the point where I was afraid to touch anything anymore.

Now I can run an up-to-date Plex! And Chrome Remote Desktop! Without spending 3 whole weekends knee deep in nix guts!

Cyph0n2• 2 years ago

There is a middle ground imo: run your application/services as containers on top of NixOS. Granted, this doesn’t work for all cases.

kstenerud8• 2 years ago

That's basically what I was doing. But it still became too stressful to manage them.

Proxmox has its own issues (they all do), but it's a much more inviting experience and nicer community.

anon2919• 2 years ago

As an opposing viewpoint, I migrated all my self hosted systems (physical machines in a data center) to use nixos and have truly reached self-hosting nirvana. Nothing breaks because I build everything before deployment, and when things do break during system build, it's fairly trivial to fix. I've successfully run all my own infrastructure on NixOS for about 5 years now. No downtime. Very easy to replace computers

tonygiorgio• 2 years ago

The OP’s article mostly seemed to be about disk space size, specifically when creating a bunch of micro vms. As a NixOS personal dev user, I’m curious about your insights here. Do you have other issues besides the disk space one? I’ve always wanted to do a NixOS server but I only know enough nix to get by on a dev machine. I’m worried about the complexity in deploying a live server.

kstenerud8• 2 years ago

NixOS is EXTREMELY opaque and obtuse. The documentation also, since everything assumes that you already know everything.

I thought that I could just power through it, but there's just no end to the edge cases, bizarre magic, lack of useful error feedback (if any at all - the most common result is: nothing happens), and situations where you simply cannot do what you want to do.

So you either conform to their model and live with the limitations (and spend countless weekends debugging your builds), or you give up and move on.

I just got tired it all. I want to spend my time USING the computer, not setting it up. So now I use Debian, because everything includes a build for Debian and drivers for Debian. And the best part is: SOMEONE ELSE is maintaining it and keeping it current with the latest security fixes.

arianvanp4• 2 years ago

I don't know any other OS where you could even go on such a trip so easily! Figuring out why things are where and being able to disable them like this is pretty cool.

I was really surprised you were able to replace systemdMinimal with systemd in dbus though.

I thought it was there to break the cyclic dependency between systemd and dbus

rollcat2• 2 years ago

Depends on what you consider "easy"! Nix itself has a pretty high barrier to entry.

Personally I believe systems that start simple (e.g. Alpine) are easier to mess with. Plus you don't have to give up all benefits of declarative configuration; for example apk has a single file (/etc/apk/world) that defines the exact package set that needs to remain installed. You can edit it and run "apk fix", much like you can edit /etc/nixos/configuration.nix and rerun "nixos-rebuild switch". It's not as powerful as Nixos, but power (and complexity) always has a price.

a_t48• 2 years ago

This reminds me a little bit of trying to slim Docker images.

aos• 2 years ago

Have you taken a look at https://github.com/nix-community/srvos ? It’s a collection of profiles for servers by the Numtide folks.

contrarian1234• 2 years ago

How "stable" are these kinds of slimming tweaks though? In a rolling release setup, aren't you going to have extraneous packages semi-regularly drag in all of Python or Perl accidentally? The setup might break and you'd not even notice?

I find the premise of a carefully re-compilable/re-creatable system very appealing, but not having a stable LTS style release rather incongruous. It takes a huge effort to get all the pieces working together - and if it's rolling and the sand is shifting/breaking underneath you it feels you never reach a meaningful stable system. Sure you can recreate your well tested working configuration, but the configurations is effectively immediately out of date and unmaintained once any packages are updated

I think this is why they effectively only target x64. I'm not a "distro guy" so maybe I'm missing something. It seems it'd be sensible to just 1-to-1 copy Ubuntu LTS package versions (+ patches) and build a NixOS "stable" version that can be patched and updated as people find issues

tkz13125• 2 years ago

NixOS has stable releases built every 6 months.

soraminazuki3• 2 years ago

I think this is why they effectively only target x64

Nix and Nixpkgs is the best in class when it comes to cross platform & cross architecture support. It has good support for x86_64 / aarch64 /macOS / Linux. Getting Musl or static variants of existing packages just work for many packages. There's even some work on BSD / Windows support. Cross compiling is far easier to setup compared to other package managers. If anything, other projects should be copying what Nix is doing.

mst• 2 years ago

NetBSD's pkgsrc has always done extremely well for me for that.

I'm not sure how feasible it would be to compare nixpkgs and pkgsrc given how different they are, but I'd encourage people who need that to poke around at both and see which one feels like a better fit for their use case.

viraptor3• 2 years ago

Almost all of the changes flip an official setting. Those stay around for a long time and get a proper deprecation notice when they go away, so you won't be surprised. Replacing systemd-minimal with the full version may potentially cause some edge case issues, but it's the same package with more features enabled, so I wouldn't really expect any.

Nothing will break when the package gets updated as long as you keep to your specific release - backported changes are backwards compatible.

steeleduncan2• 2 years ago

What is the security update policy with NixOS? I've always had the impression that I would need to upgrade every 6 months to keep getting critical security fixes, which is unappealing compared to e.g. Debian + Nix

I know I can revert easily if there are problems when upgrading, but that doesn't really apply if security fixes only land in the new branch

viraptor3• 2 years ago

You get backported security fixes in release channels as well. Unless anything changed recently, there's no explicit guarantee around them, but the core packages typicaly land just as fast or faster then other distros. Keep in mind though that more esoteric software with a small number of users and auto-update disabled may lag a bit.

steeleduncan2• 2 years ago

Maybe I'm missing something, but the only branch in github:nixos/nixpkgs I can see receiving fixes is the 24.05 branch getting fixes backported from unstable. The last commit I can see to the 23.11 branch is about 3 months ago

This would imply only 9 months of security patches before I would need to upgrade the server. That is of course a far less risky process with NixOS, so perhaps that is ok, but it is a lot more work than the 5 years you get (free) with Ubuntu/Debian

https://github.com/NixOS/nixpkgs/branches/active

wg03• 2 years ago

On borderline, thinking to learn nix. Few questions:

Can I define VM images with nix? Can those VM images be loaded into VirtualBox? Also, possible to do similar to build AMIs or other cloud VMs such as Hetzner where my "Dockerfile" is a nix file which defines the system to be built and then it has everything in place once built including tools, libraries, configuration and such?

Thoughts?

EDIT: Typos

tkz13125• 2 years ago

yes to all.

https://github.com/nix-community/nixos-generators

gallexme• 2 years ago

And for cloud/dedicated servers perhaps https://github.com/nix-community/nixos-anywhere

(There's also a terraform module ) And for state changes https://github.com/serokell/deploy-rs Or Colmena /nixops/ and x other

For secret handling perhaps https://github.com/ryantm/agenix/ + https://github.com/oddlama/agenix-rekey

The ecosystem is in my experience very well fleshed out (7 yrs of use), as long as you don't require a knowledgebase/wiki/ up2date documentation, it's not been a issue for me since I could always fall back on Linux knowledge and just looking for how other distributions do x / how the thing itself is configured , and looking at how perhaps a existing nix module wraps that

arianvanp4• 2 years ago

Yep for sure! We even have a neat upload-ami cli tool:

https://github.com/NixOS/amis

wg03• 2 years ago

That's awesome! I think all the missing pieces are in place. :)

JamesSwift2• 2 years ago

Yes but with an asterisk. Nixos generators linked elsewhere is a really great tool to take a given nix configuration and build it for consumption in many contexts (eg i use the same one to both build initial proxmox vm images and then also update those running images). The problem is that you will need a hardware-configuration.nix that caters to the end environment. Ive worked around this by pre-generating it and then copying it into the result but I wish there was a better, less manual, process.

rendaw3• 2 years ago

After the blog post the system was around 600mb, but what would be a reasonable image size for a server? Also is this bare metal or in the cloud (for the worker machines)?

kkfx4• 2 years ago

NixOS IME have few issues:

- a language friendly as Haskell, so while fit for purpose definitively it's not well digested by most, also by various longtime NixOS users;

- an unclear direction, there are countless of "side projects" and no clear path, most are not even indexed in a wiki page so you just discover by accident interacting with someone else or after a search;

- a terrible documentation probably due to the lack of a clear direction stated above.

The biggest "mean install" is true, but it's not that much impacting in the real world, NixOS real purpose is AVOIDING containers in designing an infra, not being wrapped by them or wrapping them and true x86 zero-overhead virtualization does not exists. So far only IBM Power Systems with AiX seems to have something nearly-zero-overhead built-in in the (big)iron.

IMVO that's the main point: most people, NixOS devs included, fails to see a world different than the current one. A possible answer could be keeping up the evolution of zfs and mirror some IllumOS features so we can have light paravirtualization thanks to zones on zfs clones. But as per NixOS most people fails to see a different storage than the most common today, a relict model from the '80s (does anyone remember the infamous "zfs is a rampant layer violation" phrase?). A damn real modern system should be: a SINGLE application, yes, the OS as a framework, development environment who produce a running system live out of itself. A coupled package-manager/installer/storage, because those are effectively a unique thing so we do not need a network of symlinks or containers, we have a storage behind that simply expose needed software pieces together, also a system who manage in-memory stuff the same way. Zfs was the first step in this direction, with boot environments, clones, zones glued by the Image Package System, lacking the language for a proper system integration, unfortunately almost nobody have taken care of that. NixOS and Guix System offer another piece, the language to integrate package management, installers but they lack the storage integration to generate a unique new system model.

Rediscover IllumOS (OpenSolaris) would bridge the gap providing all needed piece to start a new kind of distro and infra management for a FLOSS world where there is no need of monsters to deploy simple infra and those simple tools could scale at monster level, killing the commercial IT model of the giants and given the humanity the desktop model, the "pioneering internet" of interconnected personal system model a new start.

The lack of independent universities, big labs, is probably the root cause but as always good things tend to happen anyway sooner or later, it's the interim the bad part.

SuperSandro20009• 2 years ago

Haskell is so much worse with its custom operators.

So a vibrant community is now bad? Also there where big improvements in the last years like freeform settings.

Try reading Debians Postgres Documentation and you get a sense what terrible doc is. Not only do they point to each withput instructions but they are also about 9.5 which is stone age old.

kkfx4• 2 years ago

So a vibrant community is now bad?

It's not bad experimenting, but a thing is experimenting and have a mainline with a clear path, another is having only experiments, mostly undocumented, hard to discover, and so on.

What most people want from a distro? Being rock solid and functional with the minimum effort for anything. NixOS offer that formally, well, stating it's legacy because Flakes are the future, but their are still not there, than NixOps/Disnix and so on, this does not play with this other etc etc etc. Essentially a generic user, not a developer, have hard time to craft a stable infra with stable tech and so most fear the change reducing the community to a nearly devs-only show and enterprise player show.

Debian docs in general aren't excellent but Debian is a well known dinosaurs so most of it's users already know it, there is no need to teach anything to most, those who do not know simply ask their side friend. NixOS while not new it's still unknown to many so it have to teach well from zero various people, who aren't interested in NixOS development itself but only in it's use, model, that will contribute with return of experience, translations, casual patches and no more. They might be seen as a burden to devs, but they are "the base" that grant any distro enough popularity to really thrive.

Ubuntu back than succeed over Debian because of that. They gives a sane, ready-to-work base. There is no need to a NixOS GUI installer or so, that's not a potential target, but there is a damn need to tell anyone "start with that, learn that, in 5 and 10 years it will be the same evolved properly" No one want to learn and relearn things.

mtndew4brkfst2• 2 years ago

Re: unclear direction - I have never encountered another ecosystem more prone than Nix is to have people (and startups) trying to build their own little technical/commercial/social fiefdoms around some specific idea that X is the One True Way to do Y. Fragmentation is pervasive and detrimental and one of the major reasons I'm moving away from the tech, second only to governance.

gunalx• 2 years ago

But why would you run nixos as a micro vm os. It is not really designed for that purpose.

Nixos as a general purpose headless server OS with nix defined services, or as a desktop system with declarative and portable config is pretty neat.

jokethrowaway• 2 years ago

Nix tries to be too many things with too little resources.

As a language it's plagued by very sparse documentation. As an package manager, it still has the same issues with documentation, (compounded by tools providing the same functionality superseding each other) and then it requires maintaining EVERY software package ever created.

I think the base idea is great, the language is a little weird (but manageable), the DX is unintuitive and badly documented.

The killer reason that made me abandon NixOs is packages not being up to date. I can't fix that and I don't want to spend my life writing my own derivations when the alternative is to use Arch repos + AUR for exotic stuff.

flurie• 2 years ago

I'm not sure if this approach is being used already or even viable, but there are good tools for the following:

- creating minimal OCI images from Nix packages

- creating microvms from OCI images

There are certainly some tradeoffs with this approach, but given that the author is trying to optimize for size, in addition to one of the primary benefits to this approach being a really clean, structured build/deploy loop, it seems like it could be worth exploring.

c1yd3i• 2 years ago

Yes: https://nix.dev/tutorials/nixos/building-and-running-docker-...

They OCI images generated are super light weight.

NixOS is a good server OS, except when it isn't

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