How to create a bootloader on an usb-stick that boots a partition on a hard drive?

Question

I received an HP Elitebook Folio 9470m with Ubuntu Bionic Beaver installed on it. I installed the latest Ubuntu. After reinstalling the laptop and rebooting, the BIOS refused to boot: PXE-E61 Media Failure Check Cable - PXE-M0F Boot Device not Found Hard Disk Error 3F0. The harddrive is ok (tested with the BIOS itself), but the password of the BIOS is lost!

I observed that when a Live-usb_stick is present at power-up, that the computer is automatically booting from that stick! The idea is now to use a small usb-stick (4G) with a bootloader on it. The computer will call the bootloader (as it calls the live-usb-stick). The bootloader must then jump to the installed LM-partition on the hard drive. In this way the computer can be used again. Any ideas how to create such a bootloader?

Answer 1

Method 2

If you want a USB that just boots to GRUB see: https://askubuntu.com/a/1269476/43926. the download, https://phillw.net/isos/linux-tools/uefi-n-bios/dd_grub-boot-template-for-uefi-n-bios.img.xz will produce a USB that only boots to GRUB, There is no OS. It is easy to use it to boot ISO's, hard drives, etc.

Answer 2

Boot a Partition on a Hard Drive from an USB stick

I do this on my office computer because I don't want to mess up it's Windows boot loader.

Step by Step

1. Create a Full install USB similar to https://askubuntu.com/a/1403793/43926.

2. Use Windows Disk Management to create a partition the size you want on the hard drive, (~50Gb).

3. Boot a Live USB and use GParted to copy the Full Install's / partition to the new hard drive partition.

4. Boot the Full Install USB and run sudo update-grub.

5. The next time you boot the Full Install USB, you will be given the choice to boot Windows or the new Ubuntu partition.

I have not tried this with 22.10, 23.04 or 23.10 yet.

Since you are already running Ubuntu 23.10 on the hard drive, and not Windows, the procedure should be similar.

1. Plug in a Full Install USB, update GRUB, and you should have the option to boot any OS that is on the hard drive.

I don't think that you can update-grub on a live USB.