os-prober Just a Rant

[Peter Ehlert]

updates cause my edits to be overwritten... that sucks

# If your computer has multiple operating systems installed, then you
# probably want to run os-prober. However, if your computer is a host
# for guest OSes installed via LVM or raw disk devices, running
# os-prober can cause damage to those guest OSes as it mounts
# filesystems to look for things.
GRUB_DISABLE_OS_PROBER=false

perhaps someone should fix that other crap and leave us normal people alone

end of rant

[Andrea Borgia]

updates cause my edits to be overwritten... that sucks

Ah, ok, I wasn't seeing ghosts, then!

 

[Cindy Sue Causey]

On 5/25/23, Andrea Borgia <and...@borgia.bo.it> wrote:
>> updates cause my edits to be overwritten... that sucks
>>
>>
> Ah, ok, I wasn't seeing ghosts, then!

Last time you all chatted this up, I went in and poked around. Now
that GRUB is FINALLY working again, it's only registering one
operating system. That's after changing GRUB_DISABLE_OS_PROBER to
false here, too.

We do have the /etc/grub.d/40_custom and friends route, but my brain
hasn't been in a place to make use of that helpful feature again. My
old copies that would short track remembering how to do that are
trapped on a hard drive. It suffered a hopefully correctable
hibernation fail k/t Microsoft on a newly arrived secondhand desktop.

In the meantime of fixing that, LILO's config keeps coming back to
mind to further confuse the issue. Although.. glass half full on LILO
is that it was my first experience with changing the appearance of a
bootloader's welcoming screen. Just yesterday I almost started poking
around in GRUB's [dependencies] to attempt altering its appearance,
too. GRUB's latest update reminded that it was a to-do item
to-attempt.

Today is the first time I comprehended this part: "[R]unning os-prober
can cause damage to those guest (e.g. LVM) OSes as it mounts

filesystems to look for things."

Now I understand why that change occurred. I've noticed blips
indicating other programs were triggering partitions to mount but
never thought about the possibility of that action inflicting damage.
Good to know for programs beyond GRUB....

Cindy :)
--
Talking Rock, Pickens County, Georgia, USA
* runs with birdseed *

[Max Nikulin]

On 26/05/2023 00:16, Peter Ehlert wrote:
> updates cause my edits to be overwritten... that sucks

Do you mean the following bookworm update?

grub2 (2.06-4) unstable; urgency=high

* Add a commented-out GRUB_DISABLE_OS_PROBER section to
/etc/default/grub to make it easier for users to turn os-prober
back on if they want it. Closes: #1013797, #1009336

-- Steve McIntyre <93...@debian.org> Wed, 14 Sep 2022 22:35:49 +0100

> # If your computer has multiple operating systems installed, then you
> # probably want to run os-prober. However, if your computer is a host
> # for guest OSes installed via LVM or raw disk devices, running
> # os-prober can cause damage to those guest OSes as it mounts
> # filesystems to look for things.
> GRUB_DISABLE_OS_PROBER=false

There are people who wants other OSes to be discovered and added to boot
menu. That is why any default value is not suitable for a fraction of
users. Besides GRUB_DISABLE_OS_PROBER, there is GRUB_OS_PROBER_SKIP_LIST
for more granular selection, see

info '(grub) Simple configuration'

https://www.gnu.org/software/grub/manual/grub/html_node/Simple-configuration.html

If you do not need os-prober, it seems you can just remove the package.

Are your complains caused by changes when os-prober was disabled for
security reasons (it was announced in the NEWS file)

https://lists.ubuntu.com/archives/ubuntu-devel/2021-December/041769.html

and the following changes to partially revert such decision (see bug
reports mentioned in changelog entries)?

> perhaps someone should fix that other crap and leave us normal people alone

What fix do you expect? I see at least the following attempt

grub2 (2.06-9) unstable; urgency=medium
* Add debconf logic for GRUB_DISABLE_OS_PROBER to make it easier to
control things here. Particularly useful for the installer.
Closes: #1031594, #1012865, #1025698.

-- Steve McIntyre <93...@debian.org> Thu, 20 Apr 2023 20:35:11 +0100

[Hans]

Am Donnerstag, 25. Mai 2023, 19:16:29 CEST schrieb Peter Ehlert:
After upgrade to bookworm, the file /etc/default/grub
was overwritten. It misses the entry like the former post mentioned.

You will have to add it manually. After this, other OS are beeing seen.

Do not know, why the maintainer did delete this entry, he mighjt have his
reasons. However, if you miss this change you are confused at the first time.

Just wanted to inform other people.

Best regards and happy hacking

Hans

[Joe]

On Fri, 26 May 2023 11:28:04 +0200
Hans <hans.u...@loop.de> wrote:

> Am Donnerstag, 25. Mai 2023, 19:16:29 CEST schrieb Peter Ehlert:
> After upgrade to bookworm, the file /etc/default/grub
> was overwritten. It misses the entry like the former post mentioned.
>
> You will have to add it manually. After this, other OS are beeing
> seen.
>
> Do not know, why the maintainer did delete this entry, he mighjt have
> his reasons. However, if you miss this change you are confused at the
> first time.
>
> Just wanted to inform other people.
>

It's just the standard overwriting of configuration files during
upgrade. Apt normally warns if the new version differs from the old
and asks which you want to keep, but it's not always a simple decision
and sometimes keeping the old file causes the program itself not to
work.

There is an etc/default/grub.d, which by analogy with other xxxx.d
directories, can contain user overrides which are not touched by
upgrades, but I made a quick attempt here which failed and I didn't
have time to mess around with it. I can't find an example of doing it
correctly on the Net, which is surprising, all the references I find
are just for /etc/default/grub. Maybe someone here knows the right way?

--
Joe

[bw]

> There is an etc/default/grub.d, which by analogy with other xxxx.d
> directories, can contain user overrides which are not touched by
> upgrades, but I made a quick attempt here which failed and I didn't
> have time to mess around with it. I can't find an example of doing it
> correctly on the Net, which is surprising, all the references I find
> are just for /etc/default/grub. Maybe someone here knows the right way?
>
> --
> Joe

$ cat /etc/default/grub.d/grubtweak.cfg
# If you change this file, run 'update-grub' afterwards to update
# /boot/grub/grub.cfg.
# For full documentation of the options in this file, see:
#   info -f grub -n 'Simple configuration'

# see /etc/grub.d/40_custom
GRUB_DEFAULT=plasma

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash ipv6.disable=1 loglevel=3 acpi_backlight=vendor"

# use video=SVIDEO-1:d to fix screen flicker prob on two screens w/ plasma desktop
# can do this in 40-custom, SVIDEO-1 does not appear in fluxbox?
# i915 is broken, disabling video outputs doesn't work

GRUB_DISABLE_RECOVERY="true"

#GRUB_DISABLE_SUBMENU=y

GRUB_DISABLE_OS_PROBER="true"

[Joe]

Thank you.

--
Joe