Package request: k0s

[TECHNOFAB11]

Project description

"k0s - The Zero Friction Kubernetes" Combines multiple components of Kubernetes into a single small binary.

Metadata

• homepage URL: https://k0sproject.org
• source URL: https://github.com/k0sproject/k0s
• license: Apache License 2.0
• platforms: as far as I can see unix, linux, darwin

I quickly tried to package it using buildGoModule but this seems to be more complicated than that (they use docker and extremely hard to read Makefiles to build) because a simple go build . fails aswell. Not sure if it's a good idea to just create a derivation which calls make as this needs docker etc. which isn't quite the nix way :D Ideas welcome :)

[johbo]

Just wanted to try out k0s on a spare NixOS system of mine, realized that the imperative installation method is not working because k0s install tries to write into /etc/systemd/system/k0scontroller.service.

I got it to start with the following unit configuration injected via my configuration.nix:

  systemd.services.k0scontroller = {
    description = "k0s - Zero Friction Kubernetes";
    documentation = [ "https://docs.k0sproject.io" ];
    path = with pkgs; [
      # It wants to use "modprobe" to load kernel modules
      kmod
      # Using "mount"
      util-linux
    ];
    after = [ "network-online.target" ];
    wants = [ "network-online.target" ];
    wantedBy = [ "multi-user.target" ];
    startLimitIntervalSec = 5;
    startLimitBurst = 10;
    serviceConfig = {
      RestartSec = 120;
      Delegate = "yes";
      KillMode = "process";
      LimitCORE = "infinity";
      TasksMax = "infinity";
      TimeoutStartSec = 0;
      LimitNOFILE = 999999;
      Restart = "always";
      ExecStart = "/usr/local/bin/k0s controller --config=/etc/k0s/k0s.yaml --data-dir=/var/lib/k0s --single=true";
    };
    unitConfig = {
      ConditionFileIsExecutable = "/usr/local/bin/k0s";
    };
  };

[TECHNOFAB11]

I actually managed to at least build k0s: https://gitlab.com/TECHNOFAB/nix-packages/-/blob/main/pkgs/k0s/default.nix It's not very nice because I had to give it pkgs.kubernetes and I'm not sure if thats optimal. Wasn't able to get it working yet though, though downloading k0s and using that didn't work either, so I might have done something wrong. If anyone wants to test feel free to use my derivation (saying cuz there's no license in that repo)

[usmcamp0811]

using the above derivations I was able to get my node to join the cluster but am running into CNI issues trying to get Flannel working... I think. I installed cni-plugin-flannel and I'm going down that path to see what I need to do..

EDIT: I figured out the problem it was a PATH issue. I did this and things started working:

    systemd.services.k0sworker = {
      description = "k0s - Zero Friction Kubernetes";
      documentation = [ "https://docs.k0sproject.io" ];
      after = [ "network-online.target" ];
      wants = [ "network-online.target" ];
      serviceConfig = {
        ExecStart = "${pkgs.campground.k0s}/bin/k0s worker --token-file=/config/workertoken";
        Restart = "always";
        Environment = "PATH=/run/wrappers/bin/:$PATH";  # Add this line

      };
      wantedBy = [ "multi-user.target" ];
    };

my config is located here. I'm still cleaning up and see if there is anything else that was actually required..

[nxy7]

It might not be very helpful, but it can maybe be easier to try using k0s with cilium (installed via helm) as CNI and kube-proxy replacement, just to make sure that everything else is working correctly.

[johbo]

I've started a small Nix Flake on this based on the work of the other collaborators of this PR. It contains the proposed binary packaging and a start of a NixOS module.

https://github.com/johbo/k0s-nix