[ubuntu-studio-devel] Multiboot USB help

[Ross Gammon]

Hi All,

In preparation for building my new test machine, I created a Multiboot
USB with Debian, Ubuntu & Ubuntu Studio on it. I created it from my
normal Ubuntu desktop with grub-install & grub-mkconfig (with i386
target for maximum compatability), and then deleted everything in
grub.cfg except for the first grub.d/00_header.

Grub (with a manually produced grub.cfg) manages to boot Debian Live &
Ubuntu Live as a loopback fine, but I have tried all sorts of things to
get Ubuntu Studio Live booting and failed, and Mr Google has not helped.
I get a kernel panic (kernel panic-not syncing: VFS: unable to mount
root fs on unknown block). Maybe there is a special incantation for the
low-latency kernel when running US Live? Maybe instead of the standard
grub.d/00_header, there is special incantation I need from our livecd
script?

Has anybody tried this and succeeded?

For reference, the grub.cfg (as it currently stands) is below.

Cheers,

Ross

grub.cfg:
#
# DO NOT EDIT THIS FILE
#
# It is automatically generated by grub-mkconfig using templates
# from /etc/grub.d and settings from /etc/default/grub
#

### BEGIN /etc/grub.d/00_header ###
if [ -s $prefix/grubenv ]; then
  set have_grubenv=true
  load_env
fi
if [ "${next_entry}" ] ; then
   set default="${next_entry}"
   set next_entry=
   save_env next_entry
   set boot_once=true
else
   set default="0"
fi

if [ x"${feature_menuentry_id}" = xy ]; then
  menuentry_id_option="--id"
else
  menuentry_id_option=""
fi

export menuentry_id_option

if [ "${prev_saved_entry}" ]; then
  set saved_entry="${prev_saved_entry}"
  save_env saved_entry
  set prev_saved_entry=
  save_env prev_saved_entry
  set boot_once=true
fi

function savedefault {
  if [ -z "${boot_once}" ]; then
    saved_entry="${chosen}"
    save_env saved_entry
  fi
}
function recordfail {
  set recordfail=1
  # GRUB lacks write support for lvm, so recordfail support is disabled.
}
function load_video {
  if [ x$feature_all_video_module = xy ]; then
    insmod all_video
  else
    insmod efi_gop
    insmod efi_uga
    insmod ieee1275_fb
    insmod vbe
    insmod vga
    insmod video_bochs
    insmod video_cirrus
  fi
}

if [ x$feature_default_font_path = xy ] ; then
   font=unicode
else
insmod part_msdos
insmod part_msdos
insmod lvm
insmod ext2
set
root='lvmid/c3f015-f275-5011-e5a9-1700-016c-703ccc/c3f05a-6c75-5011-e5a9-1700-016c-703ccc'
if [ x$feature_platform_search_hint = xy ]; then
  search --no-floppy --fs-uuid --set=root
--hint='lvmid/c3f015-f275-5011-e5a9-1700-016c-703ccc/c3f05a-6c75-5011-e5a9-1700-016c-703ccc'
 2c5da318-b612-41c2-ad97-d3fbc22bf206
else
  search --no-floppy --fs-uuid --set=root
2c5da318-b612-41c2-ad97-d3fbc22bf206
fi
    font="/usr/share/grub/unicode.pf2"
fi

if loadfont $font ; then
  set gfxmode=auto
  load_video
  insmod gfxterm
  set locale_dir=$prefix/locale
  set lang=en_GB
  insmod gettext
fi
terminal_output gfxterm
if [ "${recordfail}" = 1 ] ; then
  set timeout=30
else
  if [ x$feature_timeout_style = xy ] ; then
    set timeout_style=menu
    set timeout=10
  # Fallback hidden-timeout code in case the timeout_style feature is
  # unavailable.
  elif sleep --interruptible 10 ; then
    set timeout=0
  fi
fi
### END /etc/grub.d/00_header ###

submenu "Ubuntu 18.10" {
 set isofile=/Ubuntu/ubuntu-18.10-desktop-amd64.iso
 set gfxpayload=keep
 loopback loop $isofile
 menuentry "Try Ubuntu 18.10 without installing" {
  linux (loop)/casper/vmlinuz file=/cdrom/preseed/ubuntu.seed
boot=casper iso-scan/filename=$isofile quiet splash ---
  initrd (loop)/casper/initrd
 }
 menuentry "Install Ubuntu 18.10" {
  linux (loop)/casper/vmlinuz file=/cdrom/preseed/ubuntu.seed
boot=casper iso-scan/filename=$isofile only-ubiquity quiet splash ---
  initrd (loop)/casper/initrd
 }
}

submenu "Ubuntu Studio 18.04" {
 set isofile=/Ubuntu/ubuntustudio-18.04-dvd-amd64.iso
 set gfxpayload=keep
 loopback loop $isofile
 menuentry "Try Ubuntu Studio 18.04 without installing" {
  linux (loop)/casper/vmlinuz file=/cdrom/preseed/ubuntustudio.seed
boot=casper iso-scan/filename=$isofile quiet splash ---
  initrd=(loop)/casper/initrd.lz
 }
 menuentry "Install Ubuntu Studio 18.04" {
  linux (loop)/casper/vmlinuz file=/cdrom/preseed/ubuntustudio.seed
boot=casper only-ubiquity quiet spalsh ---
  initrd=(loop)/casper/initrd.lz
 }
}

submenu "Ubuntu Studio 18.10" {
 set isofile=/Ubuntu/ubuntustudio-18.10-dvd-amd64.iso
 loopback loop $isofile
 menuentry "Try Ubuntu Studio 18.10 without installing" {
  linux (loop)/casper/vmlinuz file=/cdrom/preseed/ubuntustudio.seed
boot=casper iso-scan/filename=$isofile quiet splash ---
  initrd=(loop)/casper/initrd
 }
 menuentry "Install Ubuntu Studio 18.10" {
  linux (loop)/casper/vmlinuz file=/cdrom/preseed/ubuntustudio.seed
boot=casper only-ubiquity quiet spalsh ---
  initrd=(loop)/casper/initrd
 }
}

submenu "Debian 9.5.0" {
 set isofile=/Debian/debian-live-9.5.0-amd64-gnome.iso
 loopback loop $isofile
 menuentry "Debian 9.5.0 Live" {
  linux (loop)/live/vmlinuz-4.9.0-7-amd64 findiso=$isofile boot=live
components quiet splash
  initrd (loop)/live/initrd.img-4.9.0-7-amd64
 }
 menuentry "Install Debian 9.5.0 Graphical Installer" {
  linux (loop)/d-i/gtk/vmlinuz findiso=$isofile video=vesa:ywrap,mtrr
vga=788
  initrd (loop)/d-i/gtk/initrd.gz
 }
 menuentry "Install Debian 9.5.0 Text Based Installer" {
  linux (loop)/d-i/vmlinuz findiso=$isofile
  initrd (loop)/d-i/initrd.gz
 }
}