Dual-booting solution with only one actual Grub installation

Dual-booting solution with only one actual Grub installation

[Thorsten Wilms]

Hi once again,

There's a convenient dual-booting solution that I think hasn't been 
mentioned in these circles. You can let Grub2 offer an item that will 
load another grub.cfg.

In my case, that's a Grub installed from Ubuntu, with a menu that will 
be updated in sync with kernel installation/removal, plus one "Guix SD" 
item that will lead to the known Guix SD menu, also always up-to-date, 
without an actual second Grub installation.

No manual updating, no chain-loading of one or the other from an 
independent third Grub.

Guix SD: /etc/config.scm, in operating-system:
----
(bootloader (bootloader-configuration (bootloader (bootloader (inherit 
grub-bootloader) (installer #~(const #t))))))
----

Thanks to snape in #guix. With this, /boot/grub/grub.cfg will be 
generated, but Grub won't actually be installed.


Other system with Grub in MBR, addition to: /etc/grub.d/40_custom:
----
menuentry 'GuixSD' {
   search --fs-uuid --set=root a3a97a6f-a4c9-4569-98a3-4306f4db9ff8
   configfile /boot/grub/grub.cfg
}
----
Don't forget `sudo update-grub`.

-- 
Thorsten Wilms

thorwil's design for free software:
http://thorwil.wordpress.com/

Re: Dual-booting solution with only one actual Grub installation

[Tomáš Čech]

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On Mon, Mar 12, 2018 at 07:43:39PM +0100, Thorsten Wilms wrote:
>Hi once again,
>
>There's a convenient dual-booting solution that I think hasn't been 
>mentioned in these circles. You can let Grub2 offer an item that will 
>load another grub.cfg.
>
>In my case, that's a Grub installed from Ubuntu, with a menu that will 
>be updated in sync with kernel installation/removal, plus one "Guix 
>SD" item that will lead to the known Guix SD menu, also always 
>up-to-date, without an actual second Grub installation.
>
>No manual updating, no chain-loading of one or the other from an 
>independent third Grub.
>
>Guix SD: /etc/config.scm, in operating-system:
>----
>(bootloader (bootloader-configuration (bootloader (bootloader (inherit 
>grub-bootloader) (installer #~(const #t))))))
>----

Very nice indeed! Thanks for sharing.

S_@

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Re: Dual-booting solution with only one actual Grub installation

[Martin Castillo]

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Hi,

On 12.03.2018 19:43, Thorsten Wilms wrote:
> There's a convenient dual-booting solution that I think hasn't been
> mentioned in these circles. You can let Grub2 offer an item that will
> load another grub.cfg.

I mentioned it in [0], and I think I got the idea from some other post
in guix-devel or help-guix.

Martin

[0]: https://lists.gnu.org/archive/html/guix-devel/2017-12/msg00134.html
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Re: Dual-booting solution with only one actual Grub installation

[Thorsten Wilms]

On 13.03.2018 14:23, Martin Castillo wrote:
> I mentioned it in [0], and I think I got the idea from some other post
> in guix-devel or help-guix.
> 
> Martin
> 
> [0]:https://lists.gnu.org/archive/html/guix-devel/2017-12/msg00134.html

I think I even came across that threat, but forgot about it, as it 
didn't lead to me to a complete solution.

Regarding the discussion about adding cases to --no-bootloader, I think 
this belongs into the configuration, not an option given to `guix system 
reconfigure`, which one might forget to pass all too easily.


-- 
Thorsten Wilms

thorwil's design for free software:
http://thorwil.wordpress.com/