Arch Linux

M0rtiferrimus

Member

Registered: 2013-03-03

Posts: 34

UEFI boot entry deleted on reboot

I'm trying to set up a flash drive to boot Arch. I have successfully added a UEFI boot entry for Arch using efibootmgr (see previous thread: https://bbs.archlinux.org/viewtopic.php?id=228484).
However, when I unplug my flash drive and reboot the computer, then plug it back in, the boot entry is deleted. Similarly, if I unplug the flash drive from my laptop and plug it into my desktop, the boot entry does not appear. I was under the impression that efibootmgr created a file in the EFI directory which was then read by the UEFI on boot. If this were the case, I would expect the file to remain across reboots and to function on any computer.
The boot entry is not deleted if I unplug the flash drive while the computer is powered off, then plug it back in without turning the computer back on. Why is it doing this, and how can I get the flash drive to be bootable on any UEFI-enabled computer?

Scimmia

Fellow

Registered: 2012-09-01

Posts: 13,729

Re: UEFI boot entry deleted on reboot

The "boot entry" you're talking about is written to the NVRAM on your system's mainboard, not to the drive. To get a USB drive to boot on multiple systems, the bootloader needs to be installed as the default executable (<ESP>/EFI/Boot/Bootx64.efi for most systems), and the firmware needs to be told to just boot from the USB drive.

Last edited by Scimmia (2017-08-26 04:36:22)

R00KIE

Forum Fellow

From: Between a computer and a chair

Registered: 2008-09-14

Posts: 4,734

Re: UEFI boot entry deleted on reboot

To expand on what Scimmia said, to boot in multiple computers it is as Scimmia says. The problem about the entry getting deleted on your computer is also known, some firmwares do that. From what I've seen before you may be able to make your entry "stick" if the firmware in your computer has some menu for you to change/add entries manually, if there is no such menu then you'll have to prepare the flash drive and boot as Scimmia as described.

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R00KIE
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