Re: repair broken boot record

["pelzflorian (Florian Pelz)" <pelzflorian@pelzflorian.de>]

On Wed, Oct 06, 2021 at 10:23:38AM +0200, Thomas Danckaert wrote:
> On 2021-10-05 13:04, pelzflorian (Florian Pelz) wrote:
> > On Tue, Oct 05, 2021 at 11:28:50AM +0200, Thomas Danckaert wrote:
> > > In one of the final
> > > steps, where guix tries to install the bootloader, I get the error:
> > > 
> > > /gnu/store/.../grub/i386-pc/modinfo.sh doesn't exist. Please specify
> > > --target or --directory.
> > 
> > This is strange.  When you reconfigure, Guix should print the
> > grub-install command that was used, which should include both --target
> > and --directory.
> 
> The full message is:
> 
> guix system: error: '/gnu/store/v77n5m....grub-efi-2.06/sbin/grub-install
> --boot-directory //boot --bootloader-id=Guix --efi-directory=/boot/efi'
> exited with status 1; output follows:
> 
>   /gnu/store/.../grub-install: error:
> /gnu/store/.../lib/grub/i386-pc/modinfo.sh doesn't exist.  Please specify
> --target or --directory'
> 
> Note that the grub-install command doens't contain '--target' or
> '--directory'.  (Also: my system is x64, and this seems to be for i386.
> Should there be a --target=x64_86-efi somewhere?)

Sorry, I was wrong about --target being used; looking in the Guix
source at gnu/bootloader/grub.scm
<https://git.savannah.gnu.org/cgit/guix.git/tree/gnu/bootloader/grub.scm>,
--target is only for traditional BIOS boot and not EFI boot.

Your command is correct. I checked and have used exactly the same
command successfully (I checked the install-bootloader.scm file after
reconfigure on an EFI PC), and it should install, but for you it does
not.  It is good to see the full message though.

Note that you can run exactly the same command manually, but the
result would likely be the same.


> > However, perhaps the chroot is at fault: Before chrooting to, let’s
> > say, /mnt with chroot /mnt, you need to have mounted the /dev/sdXy
> > file system with EFI on it (that which is declared in your config.scm)
> > to /mnt/boot/efi.
> 
> I have in my config 'target /boot/efi'.  My EFI partition is /dev/sda1.  If
> I mount it like
> # mount /dev/sda1 /mnt2
> (/mnt2 because I already have my /dev/sda3 partition with guix at /mnt)
> I find the following layout:
> 
> /mnt2/EFI/
>           EFI
>           grub
>           Guix
> 
> what would be the correct bind mount?  I tried
> # mount --bind /mnt2/EFI /boot/efi
> so I now have
> /boot/efi/
>           EFI
>           grub
>           Guix
> 
> Any idea if that is the desired layout?

From outside the chroot, you should

# mount /dev/sda3 /mnt
# mount /dev/sda1 /mnt/boot/efi

Regards,
Florian