System Configuration

  1. Disable cache, stale cache will prevent system from booting:

    mkdir -p /mnt/etc/zfs/
    rm -f /mnt/etc/zfs/zpool.cache
    touch /mnt/etc/zfs/zpool.cache
    chmod a-w /mnt/etc/zfs/zpool.cache
    chattr +i /mnt/etc/zfs/zpool.cache
  2. Generate initial system configuration:

    nixos-generate-config --root /mnt
  3. Import ZFS-specific configuration:

    sed -i "s|./hardware-configuration.nix|./hardware-configuration.nix ./zfs.nix|g" /mnt/etc/nixos/configuration.nix
  4. Configure hostid:

    tee -a /mnt/etc/nixos/zfs.nix <<EOF
    { config, pkgs, ... }:
    { boot.supportedFilesystems = [ "zfs" ];
      networking.hostId = "$(head -c 8 /etc/machine-id)";
      boot.kernelPackages = config.boot.zfs.package.latestCompatibleLinuxPackages;
  5. Configure bootloader for both legacy boot and UEFI boot and mirror bootloader:

    sed -i '/boot.loader/d' /mnt/etc/nixos/configuration.nix
    sed -i '/services.xserver/d' /mnt/etc/nixos/configuration.nix
    tee -a /mnt/etc/nixos/zfs.nix <<-'EOF'
    boot.loader.efi.efiSysMountPoint = "/boot/efi";
    boot.loader.efi.canTouchEfiVariables = false;
    boot.loader.generationsDir.copyKernels = true;
    boot.loader.grub.efiInstallAsRemovable = true;
    boot.loader.grub.enable = true;
    boot.loader.grub.version = 2;
    boot.loader.grub.copyKernels = true;
    boot.loader.grub.efiSupport = true;
    boot.loader.grub.zfsSupport = true;
    boot.loader.grub.extraPrepareConfig = ''
      mkdir -p /boot/efis
      for i in  /boot/efis/*; do mount $i ; done
      mkdir -p /boot/efi
      mount /boot/efi
    boot.loader.grub.extraInstallCommands = ''
    ESP_MIRROR=$(mktemp -d)
    cp -r /boot/efi/EFI $ESP_MIRROR
    for i in /boot/efis/*; do
     cp -r $ESP_MIRROR/EFI $i
    rm -rf $ESP_MIRROR
    boot.loader.grub.devices = [
    for i in $DISK; do
      printf "      \"$i\"\n" >>/mnt/etc/nixos/zfs.nix
    tee -a /mnt/etc/nixos/zfs.nix <<EOF
  6. Mount datasets with zfsutil option:

    sed -i 's|fsType = "zfs";|fsType = "zfs"; options = [ "zfsutil" "X-mount.mkdir" ];|g' \
  7. Set root password:

    rootPwd=$(mkpasswd -m SHA-512 -s)

    Declare password in configuration:

    tee -a /mnt/etc/nixos/zfs.nix <<EOF
    users.users.root.initialHashedPassword = "${rootPwd}";
  8. Install system and apply configuration:

    nixos-install -v --show-trace --no-root-passwd --root /mnt
  9. Unmount filesystems:

    umount -Rl /mnt
    zpool export -a
  10. Reboot: