[GRUB iso multiboot]

• Auto detect and create entries for .iso files in /iso/
• Preserves its boot options!
• Small and lean, few entries lots of images
• For a new iso, same script. No need to tweak around.

Guide

1. (as root) install grub into a usb stick

sudo mount /dev/sdX /mnt/multiboot
sudo grub-install --boot-directory=/mnt/multiboot/boot/ /dev/sdX # where X is your device

2. substitute the boot/ folder created by grub for this one

rsync -a grub-iso-multiboot/boot/ /mnt/multiboot/boot/

Theme

This theme was adapted from https://github.com/Dacha204/grub2-themes-Ettery

Working ISOs (check todo file for distros)

• Core-current.iso
• Fedora-Workstation-Live-x86_64-25-1.3.iso
• FreeBSD-11.0-RELEASE-amd64-bootonly.iso
• FreeNAS-9.10.2-U2.iso
• archlinux-2017.03.01-dual.iso
• bodhi-4.1.0-64.iso
• elementaryos-0.4-stable-amd64.20160921.iso
• install-amd64-minimal-20170302.iso
• linuxmint-18.1-xfce-64bit.iso
• openSUSE-Tumbleweed-NET-x86_64-Snapshot20170308-Media.iso
• systemrescuecd-x86-4.9.3.iso
• systemrescuecd-x86-5.1.0.iso

works fine, but has a custom entry.
grub can't parse its isolinux.cfg.

• ubuntu-16.04.2-desktop-amd64.iso
• void-live-x86_64-musl-20170220.iso
• debian-8.7.1-amd64-xfce-CD-1.iso

Requires grub edit in its entry.
change syslinux.cfg to one of:
   adgtk.cfg adtxt.cfg exithelp.cfg gtk.cfg isolinux.cfg menu.cfg prompt.cfg
   rqgtk.cfg rqtxt.cfg spkgtk.cfg stdmenu.cfg txt.cfg

The `include` from grub interpretation of syslinux has a different behavior than
the original.

• antergos-18.12-x86_64.iso (custom config)
• manjaro-xfce-18.0-stable-x86_64.iso
• Solus-3.9999-Budgie.iso
• antiX-17.3.1_x64-full.iso
• MX-18_x64.iso
• ubuntu-18.10-desktop-amd64.iso
• MagOS_2016.64_20181222.iso
• ROSA.FRESH.KDE.R11.x86_64.uefi.iso

NonWorking (come back to it later)

• TrueOS-Server-2017-02-22-x64-DVD.iso

takes a while to load the iso,
but then seems to hang with a black screen (where vanilla BSD goes on), not sure
try again in verbose mode

• manjaro-xfce-17.0-stable-x86_64.iso

# grub failed to parse isolinux.cfg with:
error: syntax error.
error: Incorrect command.
error: syntax error.

• Solus-2017.01.01.0-Budgie.iso

# loads isolinux.cfg ok
seems to hang after splash

• GoboLinux-016-x86_64.iso

# Boots the kernel but fails to find the root inside the iso from kernel command line.
# memdisk would probably work here...
# You can still manually mount /Mount/CD-ROM if your iso is in a compatible disk
# but fat/vfat is not one of them. (so 1/2 working)

• Mageia-6.1-LiveDVD-GNOME-x86_64-DVD.iso

Boots the kernel but fails to find the root inside the iso from kernel command line.

How

A modified autoiso.cfg (/boot/grub/scripts/autoiso.cfg) scans for .iso and .ISO files in /iso/ and creates an entry if it knows how to boot it by:

• via loopback.cfg if present (grub loopback)
• isolinux.cfg, the majority of linux ISOs use this
• custom detection for FreeBSD

Notes

• boot/ was made with a patched version of grub to add the iso as a parameter. check the patch @ linux-extra-variable.diff (The one liner patch is public domain)

• the "patch" was made against grub-2.02_rc1. got from: https://www.gnu.org/software/grub/

• memdisk is a file from syslinux project. got from: http://www.syslinux.org/

• Also check these projects, they have the same goal as this one.

  • https://github.com/thias/glim
  • https://github.com/aguslr/multibootusb,