diff options
Diffstat (limited to 'nixos/modules/installer/netboot/netboot.nix')
-rw-r--r-- | nixos/modules/installer/netboot/netboot.nix | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/nixos/modules/installer/netboot/netboot.nix b/nixos/modules/installer/netboot/netboot.nix new file mode 100644 index 00000000000..a459e7304cd --- /dev/null +++ b/nixos/modules/installer/netboot/netboot.nix @@ -0,0 +1,120 @@ +# This module creates netboot media containing the given NixOS +# configuration. + +{ config, lib, pkgs, ... }: + +with lib; + +{ + options = { + + netboot.storeContents = mkOption { + example = literalExpression "[ pkgs.stdenv ]"; + description = '' + This option lists additional derivations to be included in the + Nix store in the generated netboot image. + ''; + }; + + }; + + config = { + # Don't build the GRUB menu builder script, since we don't need it + # here and it causes a cyclic dependency. + boot.loader.grub.enable = false; + + # !!! Hack - attributes expected by other modules. + environment.systemPackages = [ pkgs.grub2_efi ] + ++ (if pkgs.stdenv.hostPlatform.system == "aarch64-linux" + then [] + else [ pkgs.grub2 pkgs.syslinux ]); + + fileSystems."/" = mkImageMediaOverride + { fsType = "tmpfs"; + options = [ "mode=0755" ]; + }; + + # In stage 1, mount a tmpfs on top of /nix/store (the squashfs + # image) to make this a live CD. + fileSystems."/nix/.ro-store" = mkImageMediaOverride + { fsType = "squashfs"; + device = "../nix-store.squashfs"; + options = [ "loop" ]; + neededForBoot = true; + }; + + fileSystems."/nix/.rw-store" = mkImageMediaOverride + { fsType = "tmpfs"; + options = [ "mode=0755" ]; + neededForBoot = true; + }; + + fileSystems."/nix/store" = mkImageMediaOverride + { fsType = "overlay"; + device = "overlay"; + options = [ + "lowerdir=/nix/.ro-store" + "upperdir=/nix/.rw-store/store" + "workdir=/nix/.rw-store/work" + ]; + + depends = [ + "/nix/.ro-store" + "/nix/.rw-store/store" + "/nix/.rw-store/work" + ]; + }; + + boot.initrd.availableKernelModules = [ "squashfs" "overlay" ]; + + boot.initrd.kernelModules = [ "loop" "overlay" ]; + + # Closures to be copied to the Nix store, namely the init + # script and the top-level system configuration directory. + netboot.storeContents = + [ config.system.build.toplevel ]; + + # Create the squashfs image that contains the Nix store. + system.build.squashfsStore = pkgs.callPackage ../../../lib/make-squashfs.nix { + storeContents = config.netboot.storeContents; + }; + + + # Create the initrd + system.build.netbootRamdisk = pkgs.makeInitrd { + inherit (config.boot.initrd) compressor; + prepend = [ "${config.system.build.initialRamdisk}/initrd" ]; + + contents = + [ { object = config.system.build.squashfsStore; + symlink = "/nix-store.squashfs"; + } + ]; + }; + + system.build.netbootIpxeScript = pkgs.writeTextDir "netboot.ipxe" '' + #!ipxe + # Use the cmdline variable to allow the user to specify custom kernel params + # when chainloading this script from other iPXE scripts like netboot.xyz + kernel ${pkgs.stdenv.hostPlatform.linux-kernel.target} init=${config.system.build.toplevel}/init initrd=initrd ${toString config.boot.kernelParams} ''${cmdline} + initrd initrd + boot + ''; + + boot.loader.timeout = 10; + + boot.postBootCommands = + '' + # After booting, register the contents of the Nix store + # in the Nix database in the tmpfs. + ${config.nix.package}/bin/nix-store --load-db < /nix/store/nix-path-registration + + # nixos-rebuild also requires a "system" profile and an + # /etc/NIXOS tag. + touch /etc/NIXOS + ${config.nix.package}/bin/nix-env -p /nix/var/nix/profiles/system --set /run/current-system + ''; + + }; + +} |