Files
nix/modules/k3s/default.nix

80 lines
2.9 KiB
Nix

{ pkgs, ... }:
{
# TODO: see if this works with podman
# TODO: check if docker/podman is enabled
# Rootless K3S
# FIXME
environment.systemPackages = with pkgs; [
k3s
rootlesskit
slirp4netns
];
# running K3S on rootless docker was causing the following error: "failed to find cpuset cgroup (v2)" (in `docker logs k3d-lab-server-0` output)
#
# see <https://docs.k3s.io/advanced#known-issues-with-rootless-mode>
# see <https://rootlesscontaine.rs/getting-started/common/cgroup2/>
# see <https://discourse.nixos.org/t/declarative-rootless-k3s/49839>
systemd.services."user@".serviceConfig.Delegate = "cpu cpuset io memory pids";
# taken from <https://github.com/k3s-io/k3s/blob/main/k3s-rootless.service> as described in <https://docs.k3s.io/advanced#known-issues-with-rootless-mode#Rootless>
systemd.user.services."k3s-rootless" = with pkgs; {
path = with pkgs; [
"${rootlesskit}"
"${slirp4netns}"
"${fuse-overlayfs}"
"${fuse3}"
"/run/wrappers"
];
# systemd unit file for k3s (rootless)
#
# Usage:
# - [Optional] Enable cgroup v2 delegation, see https://rootlesscontaine.rs/getting-started/common/cgroup2/ .
# This step is optional, but highly recommended for enabling CPU and memory resource limtitation.
#
# - Copy this file as `~/.config/systemd/user/k3s-rootless.service`.
# Installing this file as a system-wide service (`/etc/systemd/...`) is not supported.
# Depending on the path of `k3s` binary, you might need to modify the `ExecStart=/usr/local/bin/k3s ...` line of this file.
#
# - Run `systemctl --user daemon-reload`
#
# - Run `systemctl --user enable --now k3s-rootless`
#
# - Run `KUBECONFIG=~/.kube/k3s.yaml kubectl get pods -A`, and make sure the pods are running.
#
# Troubleshooting:
# - See `systemctl --user status k3s-rootless` to check the daemon status
# - See `journalctl --user -f -u k3s-rootless` to see the daemon log
# - See also https://rootlesscontaine.rs/
enable = true;
description = "k3s (Rootless)";
serviceConfig = {
# NOTE: Don't try to run `k3s server --rootless` on a terminal, as it doesn't enable cgroup v2 delegation.
# If you really need to try it on a terminal, prepend `systemd-run --user -p Delegate=yes --tty` to create a systemd scope.
ExecStart = "${k3s}/bin/k3s server --rootless --snapshotter=fuse-overlayfs";
ExecReload = "/run/current-system/sw/bin/kill -s HUP $MAINPID";
TimeoutSec = 0;
RestartSec = 2;
Restart = "always";
StartLimitBurst = 3;
StartLimitInterval = "60s";
LimitNOFILE = "infinity";
LimitNPROC = "infinity";
LimitCORE = "infinity";
TasksMax = "infinity";
Delegate = "yes";
Type = "simple";
KillMode = "mixed";
};
wantedBy = [ "default.target" ];
};
boot.kernel.sysctl = {
"net.ipv4.ip_forward" = 1;
};
}