Re: Guix/GNU/Linux multi distro + GuixSD multi-site scenario

[Alex Kost]

Christopher Allan Webber (2016-03-28 19:39 +0300) wrote:

> Alex Kost writes:
[...]
>> Hi, I also use double boot (GuixSD and ArchLinux).  I do it like this:
>> at first I never let GuixSD to reinstall grub by using --no-grub option
>> ("guix system reconfigure --no-grub ...").  Instead I installed grub
>> manually (into a separate "boot" partition) and I use my own "grub.cfg",
>> which has an entry for the latest GuixSD system.  This entry may look
>> like this:
>>
>> menuentry 'GuixSD' {
>>     search --no-floppy --label --set guix
>>     linux  /var/guix/profiles/system/kernel/bzImage --root=guix 
>> --system=/var/guix/profiles/system --load=/var/guix/profiles/system/boot
>>     initrd /var/guix/profiles/system/initrd
>> }
>>
>> My grub config¹ also has entries for a previous system generation (I can
>> boot any generation by editing a number in a grub boot menu) and for a
>> particular system (sometimes I do "guix system build …" and put the
>> result directory of this "testing" system to my grub.cfg).
>>
>> ¹ https://github.com/alezost/config/blob/master/etc/grub.cfg
>
> Hm, I think this approach is not quite as nice, IMO.

Yeah, I think it is not suitable for most people, but it is very nice
for me :-)

> One downside here
> is that by not using the grub that guix generates for you, you can't
> simply boot into a prior system revision if something goes long, which
> is a huge advantage in GuixSD.

As I wrote I can boot into any prior system simply by editing a generation
number in the grub menu.

> Here's what I do on my grub.cfg (or libreboot_grub.cfg technically):
>
>   set timeout=5
>   insmod ahci
>   insmod chain
>
>   menuentry "Guix" {
>     set root=(ahci0,msdos7)
>     configfile /boot/grub/grub.cfg
>     unset superusers  # probably not needed
>   }
>
>   menuentry "Debian" {
>     set root=(ahci0,msdos6)
>     configfile /boot/grub/grub.cfg
>     unset superusers  # probably not needed
>   }

Thanks for sharing!  I didn't think about using "configfile" before.

-- 
Alex