pyrox.dev
1# This module creates netboot media containing the given NixOS
2# configuration.
3
4{ config, lib, pkgs, ... }:
5
6with lib;
7
8{
9 options = {
10
11 netboot.storeContents = mkOption {
12 example = literalExample "[ pkgs.stdenv ]";
13 description = ''
14 This option lists additional derivations to be included in the
15 Nix store in the generated netboot image.
16 '';
17 };
18
19 };
20
21 config = {
22
23 boot.loader.grub.version = 2;
24
25 # Don't build the GRUB menu builder script, since we don't need it
26 # here and it causes a cyclic dependency.
27 boot.loader.grub.enable = false;
28
29 boot.initrd.postMountCommands = ''
30 mkdir -p /mnt-root/nix/store
31 mount -t squashfs /nix-store.squashfs /mnt-root/nix/store
32 '';
33
34 # !!! Hack - attributes expected by other modules.
35 system.boot.loader.kernelFile = "bzImage";
36 environment.systemPackages = [ pkgs.grub2 pkgs.grub2_efi pkgs.syslinux ];
37
38 boot.consoleLogLevel = mkDefault 7;
39
40 fileSystems."/" =
41 { fsType = "tmpfs";
42 options = [ "mode=0755" ];
43 };
44
45 boot.initrd.availableKernelModules = [ "squashfs" ];
46
47 boot.initrd.kernelModules = [ "loop" ];
48
49 # Closures to be copied to the Nix store, namely the init
50 # script and the top-level system configuration directory.
51 netboot.storeContents =
52 [ config.system.build.toplevel ];
53
54 # Create the squashfs image that contains the Nix store.
55 system.build.squashfsStore = import ../../../lib/make-squashfs.nix {
56 inherit (pkgs) stdenv squashfsTools perl pathsFromGraph;
57 storeContents = config.netboot.storeContents;
58 };
59
60
61 # Create the initrd
62 system.build.netbootRamdisk = pkgs.makeInitrd {
63 inherit (config.boot.initrd) compressor;
64 prepend = [ "${config.system.build.initialRamdisk}/initrd" ];
65
66 contents =
67 [ { object = config.system.build.squashfsStore;
68 symlink = "/nix-store.squashfs";
69 }
70 ];
71 };
72
73 system.build.netbootIpxeScript = pkgs.writeTextDir "netboot.ipxe" "#!ipxe\nkernel bzImage init=${config.system.build.toplevel}/init ${toString config.boot.kernelParams}\ninitrd initrd\nboot";
74
75 boot.loader.timeout = 10;
76
77 boot.postBootCommands =
78 ''
79 # After booting, register the contents of the Nix store
80 # in the Nix database in the tmpfs.
81 ${config.nix.package}/bin/nix-store --load-db < /nix/store/nix-path-registration
82
83 # nixos-rebuild also requires a "system" profile and an
84 # /etc/NIXOS tag.
85 touch /etc/NIXOS
86 ${config.nix.package}/bin/nix-env -p /nix/var/nix/profiles/system --set /run/current-system
87 '';
88
89 };
90
91}