running linux after installing a new motherboard

#author_luna #sysadmin-notes #linux #uefi

my motherboard broke, so i bought a new one and had issues getting my pre existing linux ssd to boot in it, attempted all sorts of weird BIOS settings until eviee gave me an idea:

bootloader entry is probably not installed into nvram and the bootloader itself wasnt installed as "portable"
use efi shell to run the efi executable directly

i don't really know how to get an efi shell onto a usb drive, but i do know that grub-install may have done that on the old motherboard, as i never had to worry about that before (the old motherboard was when i installed void linux on), so i continued:

what would be the idea if i get linux booting though?
will grub just slap itself into the mobo nvram afterwards?

re-run grub install
and yeah
it'll throw itself onto nvram again

maybe i could do this from voidiso??

probably

i'll experiment l8r
brain expand

the process #

• i use Ventoy on an usb drive, but it turns out the guest ISOs that it boots won't run in UEFI mode, you must have a linux livecd burned directly into the usb drive
  • if you attempt to follow this while inside Ventoy, grub-install will stop you, claiming no EFI variables are available
• once inside voidiso
  • mkdir /media/root
  • mount /dev/... /media/root
  • mount /dev/... /media/root/boot/efi
  • mount devfs, procfs, sysfs into the chroot
    • required so that the chroot knows which disks do what
    • taken from https://github.com/void-linux/void-mklive/blob/f80794ace0c8753edfd791bd1b79df2f83c88856/lib.sh#L79
    • mount -r --rbind /dev /media/root/dev --make-rslave
    • mount -r --rbind /proc /media/root/proc --make-rslave
    • mount -r --rbind /sys /media/root/sys --make-rslave
• we're ready to chroot into the existing linux disk
  • chroot /media/root
• once inside, grub-install --target=x86_64-efi --efi-directory=/boot/efi --bootloader-id=void_grub --recheck
• reboot, and for my case, the motherboard sees the void_grub boot option