Failed to install bootloader

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1

Hi,

Sorry in advance for the wall of text; I’m trying to offer as much information upfront as possible.

I’ve been running NixOS alongside Windows 10 on my PC since August 2025 with things running relatively smoothly, given that this is my first time running a Linux distro as my main OS.

They’re installed on a system that I built in 2008; the motherboard is a Gigabyte GA-X58-UD5, with no UEFI support. Each OS is installed on its own separate disk, where there’s only one partition. NixOS is installed on an SSD, on an EXT4 partition, GRUB being the bootloader.

As for the NixOS installation, it’s on 26.11pre, using the nixos-unstable channel.

I ran sudo nixos-rebuild switch --upgrade-all and everything seemed to run fine except for the last part of the output which states that it failed to install the bootloader. This is the first time I’ve had this issue and I haven’t found this exact issue elsewhere, so I’m posting here hoping that someone might help find a solution.

Running sudo nixos-rebuild switch ends in the same bootloader error

/nix/store/2ygh3qwdxsxk6b069y1m7hmkcxfh11kd-grub-2.12/sbin/grub-install: warning: this GPT partition label contains no BIOS Boot Partition; embedding won't be possible.
/nix/store/2ygh3qwdxsxk6b069y1m7hmkcxfh11kd-grub-2.12/sbin/grub-install: error: embedding is not possible, but this is required for cross-disk install.
/nix/store/3hf1jjy43a0x96lqxwh01405w2aqmvdr-install-grub.pl: installation of GRUB on /dev/sda failed: Inappropriate ioctl for device
Failed to install bootloader
Command 'systemd-run -E LOCALE_ARCHIVE -E NIXOS_INSTALL_BOOTLOADER -E NIXOS_NO_CHECK --collect --no-ask-password --pipe --quiet --service-type=exec --unit=nixos-rebuild-switch-to-configuration /nix/store/0kybfybkzhkqalz0j161qnhpydpjl33z-nixos-system-nixos-26.11pre1040357.e2587caef70c/bin/switch-to-configuration switch' returned non-zero exit status 1.

Below is the full sudo nixos-rebuild switch output

building the system configuration...
Checking switch inhibitors... done
updating GRUB 2 menu...
Warning: os-prober will be executed to detect other bootable partitions.
Its output will be used to detect bootable binaries on them and create new boot entries.
lsblk: /dev/mapper/no*[0-9]: No such file or directory
lsblk: /dev/mapper/raid*[0-9]: No such file or directory
lsblk: /dev/mapper/disks*[0-9]: No such file or directory
Found Windows 11 on /dev/sdc1
installing the GRUB 2 boot loader on /dev/sda...
Installing for i386-pc platform.
/nix/store/2ygh3qwdxsxk6b069y1m7hmkcxfh11kd-grub-2.12/sbin/grub-install: warning: this GPT partition label contains no BIOS Boot Partition; embedding won't be possible.
/nix/store/2ygh3qwdxsxk6b069y1m7hmkcxfh11kd-grub-2.12/sbin/grub-install: error: embedding is not possible, but this is required for cross-disk install.
/nix/store/3hf1jjy43a0x96lqxwh01405w2aqmvdr-install-grub.pl: installation of GRUB on /dev/sda failed: Inappropriate ioctl for device
Failed to install bootloader
Command 'systemd-run -E LOCALE_ARCHIVE -E NIXOS_INSTALL_BOOTLOADER -E NIXOS_NO_CHECK --collect --no-ask-password --pipe --quiet --service-type=exec --unit=nixos-rebuild-switch-to-configuration /nix/store/0kybfybkzhkqalz0j161qnhpydpjl33z-nixos-system-nixos-26.11pre1040357.e2587caef70c/bin/switch-to-configuration switch' returned non-zero exit status 1.

I don’t use flakes or home-manager. My entire installation is managed in configuration.nix

I’m including below the relevant bits. If more information is needed, I will paste it.

  imports =
    [ # Include the results of the hardware scan.
      ./hardware-configuration.nix
    ];

  # Bootloader.
  boot.loader.grub.enable = true;
  boot.loader.grub.device = "/dev/sda";
  boot.loader.grub.useOSProber = true;

  # Use latest kernel.
  boot.kernelPackages = pkgs.linuxPackages_latest;

  # Enable NTFS support at boot
  boot.supportedFilesystems = [ "ntfs" ];

  fileSystems."/run/media/greyhound/Stuff" =
  { device = "/dev/disk/by-uuid/52846CD6846CBE5B";
    fsType = "ntfs-3g"; 
    options = [ "rw" "uid=1000" "nofail" "x-gvfs-show"];
  };

  fileSystems."/run/media/greyhound/More" =
  { device = "/dev/disk/by-uuid/3220739120735B35";
    fsType = "ntfs-3g"; 
    options = [ "rw" "uid=1000" "nofail" "x-gvfs-show"];
  };

  fileSystems."/run/media/greyhound/Void" =
  { device = "/dev/disk/by-uuid/000064CF0064CCEA";
    fsType = "ntfs-3g"; 
    options = [ "rw" "uid=1000" "nofail" "x-gvfs-show"];
  };

  swapDevices = [ {
    device = "/var/lib/swapfile";
    size = 16*1024;
  } ];

  nix.optimise.automatic = true;
  nix.optimise.dates = [ "03:45" ];

  nix.gc = {
    automatic = true;
    dates = "weekly";
    options = "--delete-older-than 7d";
  };

  system.autoUpgrade.enable = true;
  system.autoUpgrade.allowReboot = true;
  system.autoUpgrade.channel = "https://channels.nixos.org/nixos-unstable";

  # This value determines the NixOS release from which the default
  # settings for stateful data, like file locations and database versions
  # on your system were taken. It‘s perfectly fine and recommended to leave
  # this value at the release version of the first install of this system.
  # Before changing this value read the documentation for this option
  # (e.g. man configuration.nix or on https://nixos.org/nixos/options.html).
  system.stateVersion = "25.05"; # Did you read the comment?

Below is the hardware.nix file

imports =

    [ (modulesPath + "/installer/scan/not-detected.nix")

    ];




boot.initrd.availableKernelModules = [ "uhci_hcd" "ehci_pci" "ata_piix" "ahci" "pata_jmicron" "firewire_ohci" "uas" "usbhid" "sd_mod" ];

boot.initrd.kernelModules = [ ];

boot.kernelModules = [ "kvm-intel" ];

boot.extraModulePackages = [ ];




fileSystems."/" =

    { device = "/dev/disk/by-uuid/f24c622b-bc84-410d-9dba-4ce8a03a947a";

fsType = "ext4";

    };




swapDevices = [ ];




# Enables DHCP on each ethernet and wireless interface. In case of scripted networking

# (the default) this is the recommended approach. When using systemd-networkd it's

# still possible to use this option, but it's recommended to use it in conjunction

# with explicit per-interface declarations with `networking.interfaces.<interface>.useDHCP`.

networking.useDHCP = lib.mkDefault true;

# networking.interfaces.enp4s0.useDHCP = lib.mkDefault true;

# networking.interfaces.enp5s0.useDHCP = lib.mkDefault true;




nixpkgs.hostPlatform = lib.mkDefault "x86_64-linux";

hardware.cpu.intel.updateMicrocode = lib.mkDefault config.hardware.enableRedistributableFirmware;

}

I would greatly appreciate any help towards getting this solved. As of now, I’m afraid that shutting down the system might end in not being able to boot it up again as I ran a sudo nh clean all before the upgrade-all command due to limited disk space.

Thank you!

Edit:

Fixed by using MaxHearnden’s suggestion to set the GRUB device using the disk ID instead of the disk name.
This, of course, does not solve the GPT issue but, in my case, I just needed the GRUB device to point to my NixOS device which uses MBR instead.
It would seem that the disk name had changed at some point and that led to /dev/sda no longer pointing to the correct disk.

Thank you!

1 Like
2

May I see the partitioning of /dev/sda please?

3

Yes, of course.

Mind you, sda is just for data storage. NixOS is on sdb and Windows is on sdc.

I’m not sure why sda using GPT is suddenly an issue after so many months.

sda

image
image952×652 55.2 KB

image
image952×652 62.7 KB

sdb

image
image952×652 62.1 KB

sdc

image
image952×652 63.5 KB

sdd

image
image952×652 62.5 KB

4

GRUB needs space to install the stage 1.5 bootloader on BIOS devices. On MBR partitioned disks it uses the first 1MB of the disk as this is typically left unallocated. On GPT partitioned disks, part of the first 1MB is used for partition tables so GRUB needs another space allocated for it (BIOS Boot Partition).

What might have happened is that the device order changed so e.g. sdb (an MBR disk) used to be sda, you might want to use /dev/disk/by-id to specify a stable identifier for the disk you want to install GRUB to.

2 Likes
5

It would be very strange for the device order to have changed, given that I haven’t open up the PC in years, but I did take another look in the config file and I do find it strange that the grub device is set to sda.

Would changing

  # Bootloader.
  boot.loader.grub.enable = true;
  boot.loader.grub.device = "/dev/sda";
  boot.loader.grub.useOSProber = true;

to

  # Bootloader.
  boot.loader.grub.enable = true;
  boot.loader.grub.device = "/dev/disk/by-uuid/f24c622b-bc84-410d-9dba-4ce8a03a947a";
  boot.loader.grub.useOSProber = true;

help fix the issue?

/dev/disk/by-uuid/f24c622b-bc84-410d-9dba-4ce8a03a947a is the identifier for sdb, the NixOS drive.

6
  1. While f24c622b-bc84-410d-9dba-4ce8a03a947a is the UUID for your NixOS partition, it’s sdb1 not sdc.
  2. /dev/disk/by-uuid/f24c622b-bc84-410d-9dba-4ce8a03a947a refers to a partition not a disk, GRUB on BIOS needs to be able to write to the first block of the disk.

/dev/disk/by-id appears to be able to refer to a disk, you can use ls -l /dev/disk/by-id to find an id refering to sdb.

1 Like
7

I tried to ninja edit sdc to sdb, but I wasn’t fast enough :slight_smile:

It worked!
I got sdb’s disk ID using the command above and set it as the GRUB device in the config file.

The subsequent nixos-rebuild command resulted in GNOME crashing, for some reason, but it took me straight back to the login interface. Once I logged back in, I ran rebuild again and was able to rebuild without any errors and also ran an upgrade without any issues.

I also rebooted the system a couple of times and it’s functioning properly.

Thank you very much for your help, both of you.

Have a nice weekend! :blush:

Quick edit:

I checked the disks again, out of curiosity, and the letters seem to have swapped again between reboots. The device that was previously sda is now sdd, and the Windows device is now sda, while it was previously sdc. The NixOS device went from sdb to sdc, and the final disk went from sdd to sdb.
Good thing IDs don’t change like this.

2 Likes