various updates

nixos/hosts/olympus/kubernetes/configuration.nix

@@ -2,10 +2,37 @@
 # your system.  Help is available in the configuration.nix(5) man page
 # and in the NixOS manual (accessible by running ‘nixos-help’).
 
-{ config, pkgs, ... }:
+{ config, pkgs, hosts, ... }:
+let
+  kubeMasterIP = config.deployment.targetHost; # TODO: set more reliably
+  kubeMasterHostname =
+    "${config.networking.hostName}.${config.networking.domain}";
+  kubeMasterAPIServerPort = 6443;
+in {
+  # resolve master hostname always
+  networking.extraHosts = "${kubeMasterIP} ${kubeMasterHostname}";
 
-{
-  imports = [ ];
+  # packages for administration tasks
+  environment.systemPackages = with pkgs; [ kompose kubectl kubernetes k9s ];
+
+  # Kubernetes itself
+  services.kubernetes = {
+    roles = [ "master" "node" ];
+    masterAddress = kubeMasterHostname;
+    apiserverAddress =
+      "https://${kubeMasterHostname}:${toString kubeMasterAPIServerPort}";
+    easyCerts = true;
+    apiserver = {
+      securePort = kubeMasterAPIServerPort;
+      advertiseAddress = kubeMasterIP;
+    };
+
+    # use coredns
+    addons.dns.enable = true;
+
+    # needed if you use swap
+    kubelet.extraOpts = "--fail-swap-on=false";
+  };
 
   # This value determines the NixOS release from which the default
   # settings for stateful data, like file locations and database versions
@@ -15,8 +42,5 @@
   # (e.g. man configuration.nix or on https://nixos.org/nixos/options.html).
   system.stateVersion = "23.05"; # Did you read the comment?
 
-  # Additional packages
-  environment.systemPackages = with pkgs; [ ];
-
   networking.firewall.allowedTCPPorts = [ ];
 }