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FlexQ4

Member

Registered: 2017-02-19

Posts: 271

Multi-boot issue after installing Aquarius

Hello,
after installing Aquarius on an MBR-system on sda4 besides Windows (on sda1) and Q4OS-4 "Gemini" (on sda3):
In the boot-menu there are only the entrie for Q4os - os-prober states:

Found Debian GNU/Linux 11 (bullseye) on /dev/sda3

But what's missing/expected here would also be:

/dev/sda1:Windows 7:Windows:chain

Please, how can i get back Windows on my system??
Thank you!

Last edited by FlexQ4 (Today 11:11)

q4osteam

Q4OS Team

Registered: 2015-12-06

Posts: 6,362

Website

Re: Multi-boot issue after installing Aquarius

Please run:
$ sudo os-prober
and post the output

FlexQ4

Member

Registered: 2017-02-19

Posts: 271

Re: Multi-boot issue after installing Aquarius

here it is:

[~\> sudo os-prober
[sudo] Passwort für me:
/dev/sda3:Debian GNU/Linux 11 (bullseye):Debian:linux

Weird enough: good (now old-old-old) Gemini still does find Windows:

[:~\> sudo os-prober
[sudo] Passwort für me:
/dev/sda1:Windows 7:Windows:chain
/dev/sda4:Debian GNU/Linux 12 (bookworm):Debian:linux

But for the moment (until the issue is claryfied) i won't run update-grub on Gemini...

q4osteam

Q4OS Team

Registered: 2015-12-06

Posts: 6,362

Website

Re: Multi-boot issue after installing Aquarius

Would you check, whether there is another setting:
$ grep -R "GRUB_DISABLE_OS_PROBER" /etc/default/grub /etc/default/grub.d/ 2>/dev/null

FlexQ4

Member

Registered: 2017-02-19

Posts: 271

Re: Multi-boot issue after installing Aquarius

No, only the disabling of the "DISABLE_OS_PROBER":

# grep -R "GRUB_DISABLE_OS_PROBER" /etc/default/grub /etc/default/grub.d/ 2>/dev/null
/etc/default/grub:GRUB_DISABLE_OS_PROBER=false

/etc/default/grub.d is a directory which only contains an "empty" init-select.cfg file.

q4osteam

Q4OS Team

Registered: 2015-12-06

Posts: 6,362

Website

Re: Multi-boot issue after installing Aquarius

Two things decide this, please run on Aquarius:
$ [ -d /sys/firmware/efi ] && echo "UEFI boot" || echo "BIOS boot"
$ sudo os-prober
$ sudo grep -E "os-prober|50mounted-tests|20microsoft" /var/log/syslog | tail -30
$ sudo grub-mount /dev/sda1 /mnt && ls /mnt | head && sudo umount /mnt

Background: os-prober only reports Windows on a system booted in legacy BIOS mode -
its Windows detector exits immediately when /sys/firmware/efi exists, while Linux
systems are still listed. That alone produces exactly your output. If Aquarius
booted in UEFI mode and Gemini in BIOS mode, that is the answer, and a BIOS Windows
cannot be chainloaded from an EFI GRUB anyway - Windows then has to be started from
the firmware boot menu, or Q4OS's bootloader reinstalled in BIOS mode.

Otherwise the second possibility is that GRUB cannot read the NTFS partition:
os-prober mounts partitions only with grub-mount, and skips a partition silently if
that fails. The grub-mount line above shows it. In that case, mounting the Windows
partition before updating the menu works around it:
$ sudo mkdir -p /mnt/win && sudo mount -o ro /dev/sda1 /mnt/win
$ sudo update-grub
$ sudo umount /mnt/win

Your Gemini install is unaffected either way; running update-grub there is safe.