How to Make a Multiboot ISO With GRUB

With the GRUB bootloader for Linux, you can create a multiboot system on a USB Flash drive. To save space on the Flash drive, configure GRUB to boot the operating systems from your LiveCD ISO images. Unlike multiboot hard disks, you will need to use a Flash drive with only one partition.

Instructions

1. Insert the Flash drive into an available USB port on your computer and open a terminal session.

2. Type "fdisk -l" to see the volume and device number of the Flash drive. It will look like "/dev/sdX", with X being a unique number or letter. Write down the information.

3. Type "sudo mkfs.vfat -F 32 -n MULTIBOOT /dev/sdX1" into the prompt. Replace "X" with the correct information for your drive. If you're system is not Debian-based, replace "sudo" with the root access code for your distribution.

4. Type "sudo mount /dev/sdX1 /mnt" and press "Enter."

5. Input "grub-install --no-floppy --root-directory=/mnt /dev/sdX1" and press "Enter."

6. Type "cat <<EOF> /mnt/boot/grub/grub.cfg" to create a GRUB configuration file and open it in a text editor.

7. Enter the appropriate GRUB menu entries for the ISO files you want to have on the multiboot USB drive. Every ISO file is different. In general, you need to create lines for looping the ISO image and starting the initialization file. Some distributions also require you to enter specific hardware settings.

8. Drag the ISO images to the USB drive icon on your desktop. If you don't have the ISO images you want, use "wget" from a terminal to download them.

References

• USB Pen Drive Linux: Boot Multiple ISO From USB via Grub2 Using Linux
• Panticz: MultiBoot USB With Grub2 (Boot Directly From ISO Files)