add k3s services

hosts/k3s-nixos-02/k3s.nix

@@ -0,0 +1,31 @@
+{ config, pkgs, ... }:
+
+{
+  environment.systemPackages = with pkgs; [
+    k3s
+  ];
+
+  environment.sessionVariables = {
+    KUBECONFIG = "$HOME/.kube/config";
+  };
+
+  services.k3s = {
+    enable = true;
+    role = "agent";
+    serverAddr = "https://192.168.1.89:6443";
+    tokenFile = "/var/lib/rancher/k3s/agent/token";
+  };
+
+  services.openssh = {
+    enable = true;
+    settings = {
+      PasswordAuthentication = false;
+      PermitRootLogin = "no";
+    };
+  };
+
+  networking.firewall = {
+    allowedTCPPorts = [ 10250 22 ];
+    allowedUDPPorts = [ 8472 ];
+  };
+}