infra/services/baremetal-builder/netboot.nix

150 lines
6.4 KiB
Nix

{ modulesPath, pkgs, lib, config, extendModules, ... }@node:
let
cfg = config.bagel.baremetal.builders;
in
{
config = lib.mkIf (cfg.enable && cfg.netboot) {
system.build = {
# Build a kernel and initramfs which will download the IPXE script from hydra using
# u-root pxeboot tool and kexec into the final netbooted system.
notipxe = import (modulesPath + "/..") {
system = "x86_64-linux";
configuration =
{ pkgs, config, ... }:
{
system.stateVersion = "24.11";
boot.initrd.availableKernelModules = [ "ahci" "ehci_pci" "usb_storage" "usbhid" "sd_mod" "igb" "bonding" ];
boot.kernelParams = [ "console=ttyS0,115200" "panic=1" "boot.panic_on_fail" ];
#boot.initrd.systemd.emergencyAccess = true;
networking.hostName = "${node.config.networking.hostName}-boot";
nixpkgs.overlays = import ../../overlays;
boot.loader.grub.enable = false;
fileSystems."/".device = "bogus"; # this config will never be booted
boot.initrd.systemd.enable = true;
boot.initrd.systemd.network = {
enable = true;
networks = node.config.systemd.network.networks;
netdevs = node.config.systemd.network.netdevs;
};
boot.initrd.systemd.storePaths = [
"${pkgs.u-root}/bin/pxeboot"
"${pkgs.iputils}/bin/ping"
];
boot.initrd.systemd.services.kexec = {
serviceConfig.Restart = "on-failure";
serviceConfig.Type = "oneshot";
wantedBy = [ "initrd-root-fs.target" ];
before = [ "sysroot.mount" ];
script = ''
ln -sf /dev/console /dev/tty
until ${pkgs.iputils}/bin/ping -c 1 hydra.forkos.org; do sleep 1; done
${pkgs.u-root}/bin/pxeboot -v -ipv4=false -file https://hydra.forkos.org/job/infra/main/${node.config.networking.hostName}/latest/download-by-type/file/ipxe
'';
};
boot.initrd.systemd.contents."/etc/ssl/certs/ca-certificates.crt".source = "${pkgs.cacert}/etc/ssl/certs/ca-bundle.crt";
boot.initrd.services.resolved.enable = false;
boot.initrd.systemd.contents."/etc/resolv.conf".text = ''
nameserver 2001:4860:4860::6464
'';
boot.initrd.systemd.contents."/etc/systemd/journald.conf".text = ''
[Journal]
ForwardToConsole=yes
MaxLevelConsole=debug
'';
# Provide a bootable USB drive image
system.build.usbImage = pkgs.callPackage ({ stdenv, runCommand, dosfstools, e2fsprogs, mtools, libfaketime, util-linux, nukeReferences }:
runCommand "boot-img-${node.config.networking.hostName}" {
nativeBuildInputs = [ dosfstools e2fsprogs libfaketime mtools util-linux ];
} ''
export img=$out
truncate -s 40M $img
sfdisk $img <<EOF
label: gpt
label-id: F222513B-DED1-49FA-B591-20CE86A2FE7F
type=C12A7328-F81F-11D2-BA4B-00A0C93EC93B, bootable
EOF
# Create a FAT32 /boot/firmware partition of suitable size into firmware_part.img
eval $(partx $img -o START,SECTORS --nr 1 --pairs)
truncate -s $((2081 * 512 + SECTORS * 512)) firmware_part.img
mkfs.vfat --invariant -i 2e24ec82 -n BOOT firmware_part.img
# Populate the files intended for /boot/firmware
mkdir -p firmware/EFI/BOOT firmware/loader/entries
cp ${pkgs.systemd}/lib/systemd/boot/efi/systemd-boot*.efi firmware/EFI/BOOT/BOOT${lib.toUpper stdenv.hostPlatform.efiArch}.EFI
cat > firmware/loader/loader.conf << EOF
default foo
EOF
cat > firmware/loader/entries/default.conf << EOF
title Default
linux /EFI/${pkgs.stdenv.hostPlatform.linux-kernel.target}
initrd /EFI/initrd
options init=${config.system.build.toplevel}/init ${toString config.boot.kernelParams}
EOF
cp ${config.system.build.kernel}/${pkgs.stdenv.hostPlatform.linux-kernel.target} firmware/EFI/${pkgs.stdenv.hostPlatform.linux-kernel.target}
cp ${config.system.build.initialRamdisk}/${config.system.boot.loader.initrdFile} firmware/EFI/initrd
find firmware -exec touch --date=2000-01-01 {} +
# Copy the populated /boot/firmware into the SD image
cd firmware
# Force a fixed order in mcopy for better determinism, and avoid file globbing
for d in $(find . -type d -mindepth 1 | sort); do
faketime "2000-01-01 00:00:00" mmd -i ../firmware_part.img "::/$d"
done
for f in $(find . -type f | sort); do
mcopy -pvm -i ../firmware_part.img "$f" "::/$f"
done
cd ..
# Verify the FAT partition before copying it.
fsck.vfat -vn firmware_part.img
dd conv=notrunc if=firmware_part.img of=$img seek=$START count=$SECTORS
''
) {};
}
;
};
# This is the config which will actually be booted
netbootVariant = extendModules {
modules = [
(
{ modulesPath, ... }:
{
imports = [ (modulesPath + "/installer/netboot/netboot.nix") ];
}
)
];
};
# A derivation combining all the artifacts required for netbooting for the hydra job
netbootDir = let
kernelTarget = pkgs.stdenv.hostPlatform.linux-kernel.target;
build = config.system.build.netbootVariant.config.system.build;
in
pkgs.symlinkJoin {
name = "netboot";
paths = [
build.netbootRamdisk
build.kernel
build.netbootIpxeScript
];
postBuild = ''
mkdir -p $out/nix-support
echo "file ${kernelTarget} $out/${kernelTarget}" >> $out/nix-support/hydra-build-products
echo "file initrd $out/initrd" >> $out/nix-support/hydra-build-products
echo "file ipxe $out/netboot.ipxe" >> $out/nix-support/hydra-build-products
'';
preferLocalBuild = true;
};
};
};
}