[gentoo-user] Re: Is a USB-key-to-hard-drive-tap-dance-boot possible?

[Grant Edwards]

On 2020-12-23, Walter Dnes <waltdnes@××××××××.org> wrote:

> Situation; I have a Dell XPS8940 with that abomination known as
> UEFI, and no "legacy boot". UEFI claims there are no bootable
> partitions on the hard drive (/dev/sda).  Yet it will automatically
> boot up properly from a USB key (/dev/sdb) with Gentoo minimal
> install.

Yea, where I work, we've run into similar issues with some Dell
machines that IT insisted they procure for us to use in manufacturing
as production test stations. There seems to be no way to get them to
boot Linux from internal hard-drives, though they're quite happy
booting Linux from external USB drives. After wasting days of
engineering time, we finally told IT the machines were useless to us.

> Question; is it possible to install grub/lilo/syslinux/whatever on
> the USB key (/dev/sdb) so that it boots up and hands off control of
> the boot process to the hard drive (/dev/sda1)?

Does the UEFI BIOS recognize that /dev/sda1 exists, but just isn't
bootable? If yes, then it should be possible to install Grub on a USB
key and boot a kernel on /dev/sda1. It might be simpler to just put
the kernel and initrd on the USB key also. Though boot time might be
slightly slower that way, it won't affect performance after that.

I think...

--
Grant