Unify single-node k3s configuration

nixos/configuration.nix

@@ -27,7 +27,6 @@
     ./imalison.nix
     ./internet-computer.nix
     ./k3s.nix
-    ./k3s-single-node.nix
     ./kat.nix
     ./keepbook-sync.nix
     ./keybase.nix

nixos/k3s-single-node.nix

@@ -1,233 +0,0 @@
-{
-  pkgs,
-  config,
-  lib,
-  ...
-}:
-with lib; let
-  cfg = config.myModules.k3s-single-node;
-  plugins-path = pkgs.buildEnv {
-    name = "combined-cni-plugins";
-    paths = [
-      pkgs.cni-plugins
-      pkgs.cni-plugin-flannel
-    ];
-  };
-
-  nvidia-device-plugin-version = "v0.19.1";
-
-  nvidia-device-plugin-manifest = pkgs.writeText "nvidia-device-plugin.yaml" ''
-    apiVersion: node.k8s.io/v1
-    handler: nvidia
-    kind: RuntimeClass
-    metadata:
-      name: nvidia
-      labels:
-        app.kubernetes.io/component: gpu-operator
-    ---
-    apiVersion: apps/v1
-    kind: DaemonSet
-    metadata:
-      name: nvidia-device-plugin-daemonset
-      namespace: kube-system
-      labels:
-        app.kubernetes.io/name: nvidia-device-plugin
-    spec:
-      selector:
-        matchLabels:
-          app.kubernetes.io/name: nvidia-device-plugin
-      updateStrategy:
-        type: RollingUpdate
-      template:
-        metadata:
-          labels:
-            app.kubernetes.io/name: nvidia-device-plugin
-        spec:
-          runtimeClassName: nvidia
-          priorityClassName: system-node-critical
-          nodeSelector:
-            nvidia.com/gpu.present: "true"
-          tolerations:
-            - key: nvidia.com/gpu
-              operator: Exists
-              effect: NoSchedule
-          containers:
-            - name: nvidia-device-plugin-ctr
-              image: nvcr.io/nvidia/k8s-device-plugin:${nvidia-device-plugin-version}
-              imagePullPolicy: IfNotPresent
-              command: ["nvidia-device-plugin"]
-              env:
-                - name: DEVICE_ID_STRATEGY
-                  value: uuid
-                - name: NVIDIA_VISIBLE_DEVICES
-                  value: all
-                - name: NVIDIA_DRIVER_CAPABILITIES
-                  value: compute,utility
-              securityContext:
-                allowPrivilegeEscalation: false
-                capabilities:
-                  drop: ["ALL"]
-              volumeMounts:
-                - name: kubelet-device-plugins-dir
-                  mountPath: /var/lib/kubelet/device-plugins
-                - name: cdi-specs
-                  mountPath: /var/run/cdi
-                  readOnly: true
-          volumes:
-            - name: kubelet-device-plugins-dir
-              hostPath:
-                path: /var/lib/kubelet/device-plugins
-                type: Directory
-            - name: cdi-specs
-              hostPath:
-                path: /var/run/cdi
-                type: DirectoryOrCreate
-  '';
-
-  # Test pod to verify GPU access
-  gpu-test-pod = pkgs.writeText "gpu-test-pod.yaml" ''
-    apiVersion: v1
-    kind: Pod
-    metadata:
-      name: gpu-test
-      namespace: default
-    spec:
-      restartPolicy: Never
-      runtimeClassName: nvidia
-      containers:
-        - name: cuda-test
-          image: nvidia/cuda:12.6.3-base-ubuntu24.04
-          command: ["nvidia-smi"]
-          resources:
-            limits:
-              nvidia.com/gpu: 1
-  '';
-in {
-  options = {
-    myModules.k3s-single-node = {
-      enable = mkEnableOption "single-node k3s with GPU/CDI support";
-      extraFlags = mkOption {
-        type = lib.types.listOf lib.types.str;
-        default = [];
-        description = "Extra flags to pass to k3s";
-      };
-    };
-  };
-
-  config = mkIf cfg.enable {
-    # NVIDIA container toolkit for CDI spec generation
-    hardware.nvidia-container-toolkit = {
-      enable = true;
-      device-name-strategy = "uuid";
-      mount-nvidia-executables = true;
-    };
-
-    # Ensure CDI generator has access to nvidia libs
-    systemd.services.nvidia-container-toolkit-cdi-generator = {
-      environment.LD_LIBRARY_PATH = "${config.hardware.nvidia.package}/lib";
-    };
-
-    # k3s configuration
-    services.k3s = {
-      enable = true;
-      role = "server";
-      clusterInit = true;
-
-      configPath = pkgs.writeTextFile {
-        name = "k3s-config.yaml";
-        text = ''
-          # Disable servicelb and traefik for a minimal single-node setup
-          disable:
-            - servicelb
-            - traefik
-          kubelet-arg:
-            - "eviction-hard=nodefs.available<2Gi"
-            - "eviction-soft=nodefs.available<5Gi"
-            - "eviction-soft-grace-period=nodefs.available=5m"
-        '';
-      };
-
-      extraFlags =
-        [
-          "--node-label=nixos-nvidia-cdi=enabled"
-          "--node-label=nvidia.com/gpu.present=true"
-          "--tls-san=${config.networking.hostName}"
-          "--tls-san=${config.networking.hostName}.local"
-          "--tls-san=localhost"
-        ]
-        ++ cfg.extraFlags;
-
-      # Containerd config with CDI support
-      # k3s 1.31+ with containerd 2.0 has CDI enabled by default
-      # We only need to add the nvidia runtime configuration
-      containerdConfigTemplate = ''
-        {{ template "base" . }}
-
-        [plugins."io.containerd.grpc.v1.cri".containerd.runtimes.nvidia]
-        privileged_without_host_devices = false
-        runtime_engine = ""
-        runtime_root = ""
-        runtime_type = "io.containerd.runc.v2"
-
-        [plugins."io.containerd.grpc.v1.cri".containerd.runtimes.nvidia.options]
-        BinaryName = "${lib.getOutput "tools" config.hardware.nvidia-container-toolkit.package}/bin/nvidia-container-runtime.cdi"
-      '';
-
-      gracefulNodeShutdown.enable = true;
-    };
-
-    # Make nvidia-container-toolkit available in system PATH
-    environment.systemPackages = with pkgs; [
-      nvidia-container-toolkit
-      nvidia-container-toolkit.tools
-      kubectl
-      kubernetes-helm
-    ];
-
-    # Symlink nvidia-container-runtime.cdi to system path
-    environment.etc."profile.d/k3s-gpu.sh".text = ''
-      export KUBECONFIG=/etc/rancher/k3s/k3s.yaml
-    '';
-
-    # Create systemd service to deploy the NVIDIA device plugin after k3s is ready
-    systemd.services.k3s-gpu-plugin-deploy = {
-      description = "Deploy NVIDIA device plugin to k3s";
-      after = ["k3s.service"];
-      wants = ["k3s.service"];
-      wantedBy = ["multi-user.target"];
-      path = [pkgs.kubectl pkgs.coreutils];
-      serviceConfig = {
-        Type = "oneshot";
-        RemainAfterExit = true;
-        ExecStart = pkgs.writeShellScript "deploy-cdi-plugin" ''
-          export KUBECONFIG=/etc/rancher/k3s/k3s.yaml
-
-          # Wait for k3s API to be ready
-          echo "Waiting for k3s API server..."
-          for i in $(seq 1 60); do
-            if kubectl get nodes &>/dev/null; then
-              echo "k3s API server is ready"
-              break
-            fi
-            sleep 5
-          done
-
-          if kubectl get daemonset -n kube-system generic-cdi-plugin &>/dev/null; then
-            echo "Removing old generic-cdi-plugin deployment..."
-            kubectl delete daemonset -n kube-system generic-cdi-plugin --ignore-not-found=true
-          fi
-
-          echo "Deploying NVIDIA device plugin..."
-          kubectl apply -f ${nvidia-device-plugin-manifest}
-
-          echo "Waiting for NVIDIA device plugin to be ready..."
-          kubectl rollout status daemonset/nvidia-device-plugin-daemonset -n kube-system --timeout=120s || true
-        '';
-      };
-    };
-
-    # Store test manifests in /etc for easy access
-    environment.etc."k3s/gpu-test-pod.yaml".source = gpu-test-pod;
-    environment.etc."k3s/nvidia-device-plugin.yaml".source = nvidia-device-plugin-manifest;
-  };
-}

nixos/k3s.nix

@@ -109,6 +109,10 @@ in {
       serverAddr = mkOption {
         type = lib.types.str;
         default = "";
+        description = ''
+          Existing k3s server URL to join. Leave empty for the first or only
+          server; that enables cluster initialization with no peers.
+        '';
       };
       extraFlags = mkOption {
         type = lib.types.listOf lib.types.str;

nixos/machines/nixquick.nix

@@ -24,7 +24,6 @@
   myModules.vscode.enable = true;
   myModules.kat.enable = true;
   myModules.nvidia.enable = true;
-  myModules.k3s-single-node.enable = false;
   myModules.railbird-k3s = {
     enable = false;
     serverAddr = "https://dev.railbird.ai:6443";

nixos/machines/railbird-sf.nix

@@ -49,9 +49,6 @@
   myModules.postgres.enable = true;
   features.full.enable = true;
 
-  # Fresh single-node k3s using the existing Railbird k3s module.
-  myModules.k3s-single-node.enable = false;
-
   hardware.nvidia = {
     powerManagement.enable = false;
     # Fine-grained power management. Turns off GPU when not in use.