Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.debian.user > #176759

Re: How to seperate grub devices?

Show all headers | View raw

Le 16/01/2017 à 11:56, Darac Marjal a écrit :
>
> BIOS will typically only boot from one drive (That said, both BIOS and
> UEFI often have mechanisms to choose what that drive is).

UEFI behaves differently. It mostly uses boot entries pointing at EFI 
executable files which can be located on any drive instead of boot drives.

> When grub is
> installed to a drive, it will use the grub.cfg from that drive (I'm not
> sure if that's built in, or if it's an assumption that grub makes

GRUB comes in several parts (depending on the target/architecture), 
which can be installed on different drives.

GRUB BIOS comes in three parts :
- the boot image, installed in the MBR of a drive or the PBR of a partition
- the core image, which can be installed in different places but must be 
on the same drive as the boot image
- the other files (modules, config file...) installed in /boot/grub.

GRUB EFI only has a core image installed in the EFI system partition 
mounted on /boot/efi, and other files in /boot/grub.

The core image can contain an embedded configuration, but of course it 
is not updated by update-grub.

> For that, run "dpkg-reconfigure -plow grub-pc" (or whichever build of
> grub you're using: grub-efi-*, grub-coreboot etc. Note that you're
> reconfiguring the application package itself, NOT an auxiliary package
> such as 'grub2' or 'grub' or 'grub-common'). This *should* ask you to
> which drives you want grub installed.

Only GRUB BIOS (grub-pc) asks for a boot device. GRUB EFI won't ask for 
a boot device, because it does not need to : it does not install a boot 
image, and it installs the core image in /boot/efi by default.

> If, additionally, you want Debian's grub to ONLY boot Debian and Kali's
> grub to ONLY boot Kali, then you should uninstall the "os-prober"
> package and re-run update-grub.

Alternatively you could just add GRUB_DISABLE_OS_PROBER=true in 
/etc/default/grub instead of uninstalling os-prober.

Back to linux.debian.user | Previous | Next — Previous in thread | Find similar | Unroll thread

Thread

How to seperate grub devices? Hans <hans.ullrich@loop.de> - 2017-01-14 11:00 +0100
  Re: How to seperate grub devices? Pascal Hambourg <pascal@plouf.fr.eu.org> - 2017-01-14 11:20 +0100
    Re: How to seperate grub devices? Hans <hans.ullrich@loop.de> - 2017-01-14 11:40 +0100
      Re: How to seperate grub devices? Pascal Hambourg <pascal@plouf.fr.eu.org> - 2017-01-14 12:00 +0100
  Re: How to seperate grub devices? Darac Marjal <mailinglist@darac.org.uk> - 2017-01-16 12:00 +0100
    Re: How to seperate grub devices? Hans <hans.ullrich@loop.de> - 2017-01-16 12:10 +0100
      Re: How to seperate grub devices? Darac Marjal <mailinglist@darac.org.uk> - 2017-01-16 12:30 +0100
        Re: How to seperate grub devices? Hans <hans.ullrich@loop.de> - 2017-01-16 12:50 +0100
          Re: How to seperate grub devices? <tomas@tuxteam.de> - 2017-01-16 13:00 +0100
          Re: How to seperate grub devices? Mark Fletcher <mark27q1@gmail.com> - 2017-01-16 13:10 +0100
            Re: How to seperate grub devices? "Thomas Schmitt" <scdbackup@gmx.net> - 2017-01-16 13:50 +0100
    Re: How to seperate grub devices? Pascal Hambourg <pascal@plouf.fr.eu.org> - 2017-01-16 21:50 +0100

csiph-web