[Head_on_a_Stick]

Great guide, thanks for this!

A few points, if I may:

Originally Posted by shep

cp /usr/mdec/bootx64.efi to the drive. If you are installing to one of the
quirky laptops that uses bootx32.efi, copy that too.

I think the 32-bit loader is supposed to be called bootia32.efi (at least according to the UEFI standard).

Originally Posted by shep

Edit /etc/grub.d/40_custom

#!/bin/sh
exec tail -n +3 $0
# This file provides an easy way to add custom menu entries.  Simply type the
# menu entries you want to add after this comment.  Be careful not to change
# the 'exec tail' line above.
menuentry 'NetBSD 9.2' {
         insmod part_gpt
         insmod search_fs_uuid
         insmod chain
         chainloader (hd0,gpt1)/bootx64.efi
}

If multiple drives are connected then the (hd0,gpt1) identifier might not be consistently correct.

I prefer to use this (replace $uuid with the actual UUID of the EFI system partition):

menuentry 'NetBSD' {
   search --fs-uuid --set=root $uuid
   chainloader /bootx64.efi
}

I've never needed to manually load GRUB modules. YMMV.

HTH.