Boot Multiple ISO from USB via Grub2 using Linux

Boot ISO Files directly from USB using Grub2 from Linux. Here is one way to create a Multiboot USB Flash Drive from a running Ubuntu (I used the Live CD). You may eventually need a large Flash Drive or USB Hard Drive in order to include every bootable ISO entry. I will add more Bootable ISO files to the grub.cfg file as I find time to test them. Contact me to submit working Bootable Linux ISO grub.cfg entries for inclusion.

I. Format your USB Flash Drive to use a Single Partition:

  1. Open a terminal and type sudo su
  2. Type fdisk -l (and note which device is your USB Drive)
  3. Type fdisk /dev/sdx (replacing x with your actual usb device)
  4. Type d (to delete the existing partition)
  5. Type n (to create a new partition)
  6. Type p (for primary partition)
  7. Type 1 (to create the first partition)
  8. Press Enter (to use the first cylinder)
  9. Press Enter again (to use the default value as the last cylinder)
  10. Type a (for active)
  11. Type 1 (to mark the first partition active “bootable”)
  12. Type t (for partition type)
  13. Type c (to use fat32 partition)
  14. Type w (to write the changes and close fdisk)

II. Create a Fat32 Filesystem on the USB Flash Drive:

  1. Type umount /dev/sdx1 (to unmount the mounted partition)
  2. Type mkfs.vfat -F 32 -n MULTIBOOT /dev/sdx1 (to format the partition as fat32)

III. Install Grub2 on the USB Flash Drive:

Important Note:
Old versions of grub used --root-directory=/mnt/USB
while current versions use --boot-directory=/mnt/USB/boot

If you use the wrong syntax, you will receive an error stating “Installation is impossible. Aborting

  1. Type mkdir /mnt/USB && mount /dev/sdx1 /mnt/USB (replacing x with your actual usb device)
  2. Type grub-install --force --no-floppy --boot-directory=/mnt/USB/boot /dev/sdx (replacing x with your actual USB device)
  3. Type cd /mnt/USB/boot/grub (to change directory)
  4. Type wget (to get the grub.cfg file)

IV. Adding the Bootable ISO files:

  1. Type cd /mnt/USB (assuming USB is still mounted… else repeat section III. (part 1))
  2. Simply click a tab below, and follow the instructions for each ISO Distro you would like to add.

Type wget "" -O ubuntu.iso

Or rename your existing ISO ubuntu.iso and copy it to the USB device

Adding an Unlisted ISO: To try ISO Files that are not yet listed, use the existing menuentry examples in /boot/grub/grub.cfg and append any options normally found in the distributions syslinux.cfg file on the “append” line to the “linux” line of the menu entry.

Please inform me of entries you get to work and I will add them to the list, so that others may benefit as well.

V. Last Step… Test to ensure your USB Device Boots into Grub2:

Reboot your Computer, and enter your BIOS or Boot Menu. Set the Boot Order to boot from the USB Device. Save your changes and Reboot. If all goes well, you should be presented with a Grub2 Boot Menu.