Setup mail server and restructure some things

config/hosts/iperf/configuration.nix

@@ -0,0 +1,14 @@
+{ ... }:
+{
+  boot.loader.grub = {
+    enable = true;
+    device = "/dev/vda";
+  };
+
+  networking = {
+    hostName = "iperf";
+    firewall.enable = true;
+  };
+
+  system.stateVersion = "23.05";
+}

config/hosts/iperf/default.nix

@@ -0,0 +1,7 @@
+{ ... }:
+{
+  imports = [
+    ./configuration.nix
+    ./iperf.nix
+  ];
+}

config/hosts/iperf/iperf.nix

@@ -0,0 +1,7 @@
+{ ... }:
+{
+  services.iperf3 = {
+    enable = true;
+    openFirewall = true;
+  };
+}