Re: repair broken boot record

[pelzflorian (Florian Pelz)]

On Thu, Sep 30, 2021 at 09:43:18AM +0200, Thomas Danckaert wrote:
> Hello guix-help,
> 
> my system does not boot anymore after a guix pull and system reconfigure
> (which did show a warning, see below).  It does not even enter the GRUB
> stage, I get a "Reboot and Select proper Boot device" instead.  I think the
> MBR might not have been written correctly (just a hunch, I'm no expert...).

If this system uses no old grub-bootloader but instead EFI
(grub-efi-bootloader), maybe writing the bootloader to the mainboard
failed (it is not only written to disk), perhaps because the mainboard
NVRAM is full and needs to be cleaned with efibootmgr/efivar/such
utilities.


> During reconfigure, I did get a warning that my bootloader configuration
> used 'target', which is apparently deprecated in favor of 'targets'.  I
> wasn't paying too much attention, and ignored the warning.... I don't know
> if that could be the cause of a missing or incorrect boot record?  (In that
> case, I suggest this warning should be an ERROR ;-) )

No, the old target would fall back to targets.  The warning is only a
warning that you should switch to (targets (list "…")).



> I checked using a live USB, and it seems the whole system is still there on
> the hard drive.  Is there a way to restore my system, keeping the existing
> /gnu/store?  Or do I have to reinstall from scratch, remove the existing
> /gnu/store and rebuild everything (shouldn't be too much work using Guix,
> but way less elegant :) )
> 
> Thank you!
> 
> Thomas

I search on Duckduckgo for “site:lists.gnu.org guix chroot”, you
should read there how to chroot into your system so you can
reconfigure.

Regards,
Florian