doc/src/SUMMARY.md

@@ -13,4 +13,5 @@
         - [TODO](./todo.md)
     - [How-to]()
         - [Updates](./anleitung/updates.md)
-        - [Rollbacks](./anleitung/rollback.md)
+        - [Rollbacks](./anleitung/rollback.md)
+        - [MicroVM](./anleitung/microvm.md)

doc/src/anleitung/microvm.md

@@ -0,0 +1,52 @@
+### Declaring a MicroVM
+
+The hosts nixosSystems modules should be declared using the ```makeMicroVM``` helper function.
+Use durruti as orientation:
+``` nix
+    modules = makeMicroVM "durruti" "10.0.0.5" [
+      ./durruti/configuration.nix
+    ];
+```
+
+"durruti" is the hostname.  
+"10.0.0.5" is the IP assigned to its tap interface.  
+
+### Testing MicroVMs locally
+MicroVMs can be built and run easily on your local host.
+For durruti this is done by:
+``` bash
+sudo nix run .\#nixosConfigurations.durruti.config.microvm.declaredRunner
+```
+
+It seems to be necessary to run this as root so that the according tap interface can be created.
+To be able to ping the VM or give Internet Access to the VM your host needs to be setup as described below.
+
+### Host Setup
+
+#### Network Bridge
+To provide network access to the VMs a bridge interface needs to be created on your host.
+For that:
+- Add the infrastructure flake as input to your hosts flake  
+- Add ```inputs.malobeo.nixosModules.malobeo``` to your hosts imports
+- enable the host bridge: ```services.malobeo.microvm.enableHostBridge = true;```
+
+If you want to provide Internet access to the VM it is necessary to create a nat.
+This could be done like this:
+``` nix
+networking.nat = {
+  enable = true;
+  internalInterfaces = [ "microvm" ];
+  externalInterface = "eth0"; #change to your interface name
+};
+```
+#### Auto Deploy VMs
+By default no MicroVMs will be initialized on the host - this should be done using the microvm commandline tool.
+But since we want to always deploy certain VMs it can be configured using the ```malobeo.microvm.deployHosts``` option.
+VMs configured using this option will be initialized and autostarted at boot.
+Updating still needs to be done imperative, or by enabling autoupdates.nix
+
+The following example would init and autostart durruti and gitea:
+``` nix
+malobeo.microvm.deployHosts = [ "durruti" "gitea" ];
+```
+

flake.lock

@@ -21,6 +21,24 @@
         "url": "https://git.dynamicdiscord.de/kalipso/ep3-bs.nix"
       }
     },
+    "flake-utils": {
+      "inputs": {
+        "systems": "systems_3"
+      },
+      "locked": {
+        "lastModified": 1726560853,
+        "narHash": "sha256-X6rJYSESBVr3hBoH0WbKE5KvhPU5bloyZ2L4K60/fPQ=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "c1dfcf08411b08f6b8615f7d8971a2bfa81d5e8a",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
     "home-manager": {
       "inputs": {
         "nixpkgs": [
@@ -61,6 +79,28 @@
         "type": "github"
       }
     },
+    "microvm": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": [
+          "nixpkgs"
+        ],
+        "spectrum": "spectrum"
+      },
+      "locked": {
+        "lastModified": 1731240174,
+        "narHash": "sha256-HYu+bPoV3UILhwc4Ar5iQ7aF+DuQWHXl4mljN6Bwq6A=",
+        "owner": "astro",
+        "repo": "microvm.nix",
+        "rev": "dd89404e1885b8d7033106f3898eaef8db660cb2",
+        "type": "github"
+      },
+      "original": {
+        "owner": "astro",
+        "repo": "microvm.nix",
+        "type": "github"
+      }
+    },
     "nixlib": {
       "locked": {
         "lastModified": 1729386149,
@@ -182,6 +222,7 @@
         "ep3-bs": "ep3-bs",
         "home-manager": "home-manager",
         "mfsync": "mfsync",
+        "microvm": "microvm",
         "nixos-generators": "nixos-generators",
         "nixos-hardware": "nixos-hardware",
         "nixpkgs": "nixpkgs_2",
@@ -212,6 +253,22 @@
         "type": "github"
       }
     },
+    "spectrum": {
+      "flake": false,
+      "locked": {
+        "lastModified": 1729945407,
+        "narHash": "sha256-iGNMamNOAnVTETnIVqDWd6fl74J8fLEi1ejdZiNjEtY=",
+        "ref": "refs/heads/main",
+        "rev": "f1d94ee7029af18637dbd5fdf4749621533693fa",
+        "revCount": 764,
+        "type": "git",
+        "url": "https://spectrum-os.org/git/spectrum"
+      },
+      "original": {
+        "type": "git",
+        "url": "https://spectrum-os.org/git/spectrum"
+      }
+    },
     "systems": {
       "locked": {
         "lastModified": 1681028828,
@@ -257,6 +314,21 @@
         "type": "github"
       }
     },
+    "systems_4": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
+    },
     "tasklist": {
       "inputs": {
         "nixpkgs": [
@@ -315,7 +387,7 @@
     },
     "utils_3": {
       "inputs": {
-        "systems": "systems_3"
+        "systems": "systems_4"
       },
       "locked": {
         "lastModified": 1726560853,

flake.nix

@@ -8,6 +8,8 @@
     sops-nix.url = "github:Mic92/sops-nix";
     sops-nix.inputs.nixpkgs.follows = "nixpkgs";
     mfsync.url = "github:k4lipso/mfsync";
+    microvm.url = "github:astro/microvm.nix";
+    microvm.inputs.nixpkgs.follows = "nixpkgs";
 
     utils = {
       url = "github:numtide/flake-utils";

machines/configuration.nix

@@ -40,6 +40,39 @@ let
     }
   ];
   defaultModules = baseModules;
+
+  makeMicroVM = hostName: ipv4Addr: modules: [
+    inputs.microvm.nixosModules.microvm
+    {
+      microvm = {
+        hypervisor = "qemu";
+        shares = [ {
+          tag = "ro-store";
+          source = "/nix/store";
+          mountPoint = "/nix/.ro-store";
+        } ];
+        interfaces = [
+          {
+            type = "tap";
+            id = "vm-${hostName}";
+            mac = "02:00:00:00:00:01";
+          }
+        ];
+      };
+      
+      systemd.network.enable = true;
+      
+      systemd.network.networks."20-lan" = {
+        matchConfig.Type = "ether";
+        networkConfig = {
+          Address = [ "${ipv4Addr}/24" ];
+          Gateway = "10.0.0.1";
+          DNS = ["1.1.1.1"];
+          DHCP = "no";
+        };
+      };
+    }
+  ] ++ defaultModules ++ modules;
 in
 {
   louise = nixosSystem {
@@ -53,7 +86,7 @@ in
   durruti = nixosSystem {
     system = "x86_64-linux";
     specialArgs.inputs = inputs;
-    modules = defaultModules ++ [
+    modules = makeMicroVM "durruti" "10.0.0.5" [
       ./durruti/configuration.nix
     ];
   };

machines/durruti/configuration.nix

@@ -5,7 +5,6 @@ with lib;
 {
   sops.defaultSopsFile = ./secrets.yaml;
 
-  boot.isContainer = true;
   networking = {
     hostName = mkDefault "durruti";
     useDHCP = false;

machines/durruti/host_config.nix

@@ -44,6 +44,5 @@ in
       enableACME= true;
       locations."/".proxyPass = "http://${cfg.host_ip}:80";
     };
-
   };
 }

machines/modules/malobeo/microvm_host.nix

@@ -0,0 +1,89 @@
+{ config, self, lib, inputs, options, pkgs, ... }:
+
+with lib;
+
+let
+  cfg = config.services.malobeo.microvm;
+in
+{
+  options = {
+    services.malobeo.microvm = {
+      enableHostBridge = mkOption {
+        default = false;
+        type = types.bool;
+        description = lib.mdDoc "Setup bridge device for microvms.";
+      };
+
+      enableHostBridgeUnstable = mkOption {
+        default = false;
+        type = types.bool;
+        description = lib.mdDoc "Setup bridge device for microvms.";
+      };
+
+      deployHosts = mkOption {
+        default = [];
+        type = types.listOf types.str;
+        description = ''
+          List hostnames of MicroVMs that should be automatically initializes and autostart
+        '';
+      };
+    };
+  };
+
+
+  imports = [
+    inputs.microvm.nixosModules.host
+  ];
+
+  config = { 
+    assertions = [
+      {
+        assertion = !(cfg.enableHostBridgeUnstable && cfg.enableHostBridge);
+        message = ''
+          Only enableHostBridge or enableHostBridgeUnstable! Not Both!
+        '';
+      }
+    ];
+
+    systemd.network = mkIf (cfg.enableHostBridge || cfg.enableHostBridgeUnstable) {
+      enable = true;
+      # create a bride device that all the microvms will be connected to
+      netdevs."10-microvm".netdevConfig = {
+        Kind = "bridge";
+        Name = "microvm";
+      };
+
+      networks."10-microvm" = {
+        matchConfig.Name = "microvm";
+        networkConfig = {
+          DHCPServer = true;
+          IPv6SendRA = true;
+        };
+        addresses = if cfg.enableHostBridgeUnstable then [
+          { Address = "10.0.0.1/24"; }
+        ] else [
+          { addressConfig.Address = "10.0.0.1/24"; }
+        ];
+      };
+
+      # connect the vms to the bridge
+      networks."11-microvm" = {
+        matchConfig.Name = "vm-*";
+        networkConfig.Bridge = "microvm";
+      };
+    }; 
+
+    microvm.vms = 
+    let
+      # Map the values to each hostname to then generate a Attrs using listToAttrs
+      mapperFunc = name: { inherit name; value = {
+          # Host build-time reference to where the MicroVM NixOS is defined
+          # under nixosConfigurations
+          flake = inputs.malobeo; 
+          # Specify from where to let `microvm -u` update later on
+          updateFlake = "git+https://git.dynamicdiscord.de/kalipso/infrastructure?ref=microvm";
+        }; };
+    in
+    builtins.listToAttrs (map mapperFunc cfg.deployHosts);
+  };
+}

outputs.nix

@@ -41,7 +41,7 @@ in (utils.lib.eachSystem (builtins.filter filter_system utils.lib.defaultSystems
     apps = {
       docs = {
         type = "app";
-        program = builtins.toString (pkgs.writeScript "docs" ''
+        program = builtins.toString (pkgs.writeShellScript "docs" ''
           ${pkgs.mdbook}/bin/mdbook serve --open ./doc
         '');
       };
@@ -52,7 +52,10 @@ in (utils.lib.eachSystem (builtins.filter filter_system utils.lib.defaultSystems
       inherit inputs;
     });
 
-    nixosModules.malobeo = import ./machines/durruti/host_config.nix;
+    nixosModules.malobeo.imports = [
+      ./machines/durruti/host_config.nix
+      ./machines/modules/malobeo/microvm_host.nix
+    ];
 
     hydraJobs = nixpkgs.lib.mapAttrs (_: nixpkgs.lib.hydraJob) (
       let