How can I install Ubuntu if I only have a 512MB USB stick and do not want to use Mini CD ISO,

I have a Windows 10 computer and will be using Something else for the installation.

  • Is it actually just 619 MB? That's a very non-standard size. I'd guess it's just partitioned to be limited to 619 MB, but the actual capacity is larger, in the gigabyte range, and a power of 2.
    – gronostaj
    Nov 16, 2020 at 7:22
  • @ronostaj You are technically correct, I took that number from a post that was closed as a duplicate: askubuntu.com/questions/1292260/… I think this answer is more practical than the answer referred to in the other post. I will change size of this USB to 512MB. good catch. Nov 16, 2020 at 7:41

1 Answer 1


Install Ubuntu Using a Small USB stick

The Ubuntu ISO can be installed using the grub bootloader from a USB stick. Here is a Step by Step.

  • Download the Ubuntu ISO to the Downloads folder of Windows. (There are easier methods to install Ubuntu if you already have Ubuntu).

  • Download the mkusb ISO boot template: https://phillw.net/isos/linux-tools/uefi-n-bios/dd_grub-boot-template-for-uefi-n-bios.img.xz

  • Extract the image to a minimum 250MB USB using Rufus, Etcher, mkusb, Disks, dd, etc.

  • Edit the first menu entry of usbboot/boot/grub/grub.cfg as follows

    menuentry "ubuntu.iso" {
      search --set=root --fs-uuid 20EEA649EEA61756
      set isofile="/Users/c.cameron/Downloads/ubuntu-20.10-desktop-amd64.iso"
      loopback loop $isofile
      linux (loop)/casper/vmlinuz boot=casper iso-scan/filename=$isofile toram --
      initrd (loop)/casper/initrd

    Where 20EEA649EEA61756 is the Windows partition UUID.

Reboot the computer to "ubuntu.iso" and install Ubuntu using "Something Else" as normal.

  • +2 and rendered the menuentry ascode. Comment: smart workaround when the USB drive is too small :-)
    – sudodus
    Nov 15, 2020 at 13:15
  • @sudodus: It took me a while to get around to setting root per the UUID. Trying to set root =(hd0,1), etc would not work for me? Nov 15, 2020 at 13:21
  • It can be tricky to tell how the drives are numbered as (hdx), Often the selected boot drive is (hd0), and the next one detected is (hd1), so it may work with (hd1,1) to identify the partition with the iso file, but it is much more reliable to use the UUID.
    – sudodus
    Nov 15, 2020 at 13:26
  • 1
    By the way, maybe it is a good idea to add the boot option toram in this case, since the user may want to tamper with the partition table of the drive containing the iso file. (But best practice is to use Windows to shrink the Windows partiiton and to leave the unallocated drive space as unallocated for Ubuntu to manage (either with gparted or in the installer's 'Something else' mode)).
    – sudodus
    Nov 15, 2020 at 13:35
  • @sudodus: I tried every possible combination of x and y for (hdx,y), no luck. I added toram, thank you. I prefer Windows Disk Management myself for editing Windows partitions. Nov 15, 2020 at 13:48

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.