GRUB and os-prober to detect another linux distro [SOLVED]

graysky · 2012-12-27 22:45:43

I installed os-prober alongside of grub-bios but do not understand why it won't find and create an entry for another Arch install mounted up to /mnt/otherarch

% sudo grub-mkconfig -o /boot/grub/grub.cfg
Generating grub.cfg ...
Found linux image: /boot/vmlinuz-linux
Found initrd image: /boot/initramfs-linux.img
done

I'd like to boot to the alternative Arch install (on /dev/sda5) so I can run `e2fsck -cc /dev/sda3` which is the partition on which my main install resides. Thanks!

% ls -l /mnt/otherarch/boot 
total 18580
-rw-r--r-- 1 root root 12816472 Dec 27 17:35 initramfs-linux-fallback.img
-rw-r--r-- 1 root root  2859919 Dec 27 17:35 initramfs-linux.img
-rw-r--r-- 1 root root  3340096 Dec 11 04:28 vmlinuz-linux

EDIT: I manually edited /etc/grub/40_custom to do this but isn't that what os-prober is supposed to do?

Last edited by graysky (2012-12-27 23:55:05)

cfr · 2012-12-27 23:03:21

Last I read about this, os-prober was very bad at detecting Arch installations at all. I've no idea why, though.

graysky · 2012-12-27 23:54:55

Very odd... after a reboot, it started working!

% sudo grub-mkconfig -o /boot/grub/grub.cfg
Generating grub.cfg ...
Found linux image: /boot/vmlinuz-linux
Found initrd image: /boot/initramfs-linux.img
Found Arch on /dev/sda5
done

2ManyDogs · 2012-12-28 00:16:30

cfr wrote:

Last I read about this, os-prober was very bad at detecting Arch installations at all. I've no idea why, though.

Short answer, because os-prober is a Debian thing, not an Arch thing.

Longer answer: https://bbs.archlinux.org/viewtopic.php?id=145875

cfr · 2012-12-28 00:21:10

graysky wrote:

Very odd... after a reboot, it started working!

% sudo grub-mkconfig -o /boot/grub/grub.cfg
Generating grub.cfg ...
Found linux image: /boot/vmlinuz-linux
Found initrd image: /boot/initramfs-linux.img
Found Arch on /dev/sda5
done

You mean you deleted the stuff in 40_custom and it still worked?

graysky · 2012-12-28 00:53:08

Yes.. Inspect the output in the code tags carefully.

cfr · 2012-12-28 02:25:03

It is a very long time since I ran grub-mkconfig on Arch (and I think Fedora gives different output) so I don't know whether that might not be part of your 40_custom or not. That was all.

graysky · 2012-12-28 02:40:49

It's not, I commented out the lines I added. Again, inspect the output I posted in the code tags. You'll see that the they differ after the reboot.

cfr · 2012-12-28 02:43:46

graysky wrote:

It's not, I commented out the lines I added. Again, inspect the output I posted in the code tags. You'll see that the they differ after the reboot.

You mean it didn't output anything when it found it using 40_custom? So what you posted originally was even with 40_custom?

Clearly being very dense here. Not that I'm sure it matters, especially .

graysky · 2012-12-28 10:47:36

cfr wrote:

You mean it didn't output anything when it found it using 40_custom? So what you posted originally was even with 40_custom?

Yes and yes.

...why would anything in 40_custom affect the output? Look at the code for os-prober.

Arch Linux

#1 2012-12-27 22:45:43

GRUB and os-prober to detect another linux distro [SOLVED]

#2 2012-12-27 23:03:21

Re: GRUB and os-prober to detect another linux distro [SOLVED]

#3 2012-12-27 23:54:55

Re: GRUB and os-prober to detect another linux distro [SOLVED]

#4 2012-12-28 00:16:30

Re: GRUB and os-prober to detect another linux distro [SOLVED]

#5 2012-12-28 00:21:10

Re: GRUB and os-prober to detect another linux distro [SOLVED]

#6 2012-12-28 00:53:08

Re: GRUB and os-prober to detect another linux distro [SOLVED]

#7 2012-12-28 02:25:03

Re: GRUB and os-prober to detect another linux distro [SOLVED]

#8 2012-12-28 02:40:49

Re: GRUB and os-prober to detect another linux distro [SOLVED]

#9 2012-12-28 02:43:46

Re: GRUB and os-prober to detect another linux distro [SOLVED]

#10 2012-12-28 10:47:36

Re: GRUB and os-prober to detect another linux distro [SOLVED]

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