Re: Tripple boot Debian 12, Debian 13, openSUSE EFI
On Wed, Sep 17, 2025 at 6:10 PM Richmond <dnomhcir@gmx.com> wrote:
>
> Felix Miata <mrmazda@earthlink.net> writes:
>
> > Richmond composed on 2025-09-17 18:14 (UTC+0100):
> >
> >> Why did this all go so wrong? Why would
> >> Debian 13 boot without displaying Grub, even though it had a timeout of
> >> 5 seconds?
> >
> > Grub's upstream default changed to disabling os-prober, so 13's Grub doesn't look
> > for anything else, and since the new installation had only one kernel to offer,
> > there was no reason to assume other than the sole known kernel to boot. Change
> > /etc/default/grub to enable os-prober, and following next update of grub.cfg, you
> > should find 12, 13 and openSUSE in your 13 Grub menu.
>
> I didn't find a grub menu, and os-probe was running. It was all
> puzzling.
>
> I have two EFI System partitions so this must have been the cause of the
> problem. In the old days installation used to say "you already have
> grub, do you want to overwrite it?" or something like that but there was
> no such question. Immediately after the installation I did see a Debian
> 13 grub menu, but trying to fix Debian 12 caused it to vanish and never
> come back.
>
> So how is it that re-installing grub from the boot media rescued Debian
> 12, but re-installing grub from Debian 12 did not?
Isn't the os-prober disabled nowadays? I think that would explain why
other Linux installations are not being found.
Otherwise, I think you will need to provide a lot more information.
And personally, I would not putz around with GRUB. UEFI is perfectly
capable of managing and booting multiple OSes. ... Unless there is a
specific need, like chain loading.
> At some point I did these commands which may have been a bad idea:
>
> sudo grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=debian12
> sudo update-grub
>
> >From Debian 12 I see:
> /boot/efi/EFI# ls -l
> total 20
> drwx------ 2 root root 4096 Oct 31 2014 Boot
> drwx------ 2 root root 4096 Dec 28 2023 debian
> drwx------ 2 root root 4096 Sep 17 17:13 debian12
> drwx------ 3 root root 4096 Jul 6 2014 Dell
> drwx------ 4 root root 4096 Oct 31 2014 Microsoft
>
> The Opensuse one is:
> ls -l /mnt/EFI
> total 4
> drwxr-xr-x 2 root root 2048 Apr 7 2024 boot
> drwxr-xr-x 2 root root 2048 Apr 7 2024 opensuse
Jeff
Reply to: