Boot Ubuntu live USB from GRUB2 prompt

ubuntu_logo_81x81Do you have a decade old machine that doesn’t support booting from USB? Want to try out the latest lightweight Ubuntu derivative (like Lubuntu or LXLE) on it quickly? Here’s a way to do that using live USB.


We are assuming that you do not have Ubuntu installed on the device. We need

  • A bootable CD with a relatively newer version (having GRUB2) of Ubuntu ISO burnt on it.
  • A live USB pen drive created using Startup Disk Creator on Ubuntu.


  1. Boot the device from the CD. Boot to the desktop to try Ubuntu.
  2. Create a new volume with GRUB2 installed.
    $ sudo su
    # mkdir /mnt/grub/
    # mount /dev/sda1 /mnt/grub/
    # grub-install --no-floppy --root-directory=/mnt/grub /dev/sda
  3. Attach the USB. Reboot the device into GRUB2 command mode prompt.
  4. Use the following commands to detect the USB drive and volume number for the volume created in Step 2.
    grub> ls : display volumes known to GRUB2
    grub> ls (hdX,Y)/ : display contents of hdX,Y
    e.g., to check the files on second disk, first volume
    grub> ls (hd1,0)/ //assume pen drive is sdb, with one volume
  5. Boot from the pen drive.
    grub> set root='(hd1,0)'
    grub> chainloader +1
    grub> boot

One thought on “Boot Ubuntu live USB from GRUB2 prompt”

Leave a Reply

Your email address will not be published. Required fields are marked *