Re: boot multiple Gnu/Linux Distributions from one USB key

[gnuforever]

On 12.03.2019 11:34, Tobias Geerinckx-Rice wrote:
> You'll also note that Debian-based distributions use a completely 
> different magic word:
>
>  linux … iso-scan/filename=$isofile …

Indeed. For Trisquel, libreboot, I have this:

       ## TRISQUEL
       menuentry "Trisquel 7.0 - Gnu/Linux" {
           set isofile="/boot-isos/trisquel_7.0_amd64.iso"
           loopback loop (usb0,msdos1)$isofile
           linux (loop)/casper/vmlinuz boot=casper 
iso-scan/filename=$isofile noprompt noeject timezone=Europe/Brussels
           initrd (loop)/casper/initrd
       }

> I wonder if MAPPED-DEVICES could be a solution here, with a bit (heh) 
> of extra code…

Unfortunately, I am not a lisp programmer. Not a programmer at all :-)
I do some lisp in my emacs config files but just for emacs 
customization.
Code I found from other emacs users or sometimes with the emacs 
customization wizard.

> TL;DR: there is no one reliable way, only distro-specific support.
Does this mean that ,for the moment, I can not add Guix to my multiple 
boot usb key?


On 12.03.2019 14:05, Ricardo Wurmus wrote:
> Does a partition with this label exist?

Yes, it exists. If I dd the guix install iso into a usb and boot from 
it, the /dev/sr0 which is the is it booted from has "GUIXSD_IMAGE" as 
label
In fact, the default embeded grub.cfg in the guix iso looks like this, 
but it uses uuid

        search --fs-uuid --set 1970-01-01-19-16-18-78
        linux 
/gnu/store/0zajbn9q39yva4l0zzrcshlll8qikzba-linux-libre-4.19.6/bzImage9 
--system=/gnu/store/l4hgd4l7acrqwi3imav9akcvv4sbj85j-system 
--load=/gnu/store/l4hgd4l7acrqwi3imav9akcvv4sbj85j-system/boot
        initrd 
/gnu/store/9nqaksx40zh5d6cg5rim3f3spy56bfb9-raw-initrd/initrd.cpio.gz


On 12.03.2019 19:56, Vagrant Cascadian wrote:
> From the Guix initramfs you would need to run:
>
>   losetup /path/to/file
>
> If the image was in a partitioned loopback file:
>
>   losetup --partscan /path/to/file
>
> Then I suspect the labels would get populated. You may also need to add
> losetup to the initramfs, since it probably isn't yet present.
>
> I'm guessing you would also remove the (loop) from these arguments,
> which are passed to the Guix initramfs, not loaded from grub:
>
>   --system=/gnu/store...-system
>   --load=/gnu/store...-boot

I will give a try.

Happy Gnu!
gnuforever