feat: new k3s cluster

hosts/k8s/k3s_prod_1_master_3/k3s.nix

@@ -0,0 +1,27 @@
+{
+  config,
+  pkgs,
+  vars_networking,
+  ...
+}: let
+  serverName = "k3s-prod-1-master-1";
+  serverIp = vars_networking.hostAddress.${serverName}.address;
+  package = pkgs.k3s_1_29;
+in {
+  environment.systemPackages = [package];
+  services.k3s = {
+    inherit package;
+    enable = true;
+    role = "server";
+    serverAddr = "https://${serverIp}:6443";
+    tokenFile = config.age.secrets."k3s-prod-1-token".path;
+    # https://docs.k3s.io/cli/server
+    extraFlags =
+      " --write-kubeconfig /etc/k3s/kubeconfig.yml"
+      + " --write-kubeconfig-mode 644"
+      + " --service-node-port-range 80-32767"
+      + " --data-dir /var/lib/rancher/k3s"
+      + " --etcd-expose-metrics true"
+      + '' --etcd-snapshot-schedule-cron "0 */12 * * *"'';
+  };
+}