Arch Linux

Oldiesmann

Member

Registered: 2020-04-20

Posts: 17

Lost ability to boot into Arch after Windows reinstall

I have a dual boot system with Win 11 and Arch. Long story short, I had to wipe the EFI partition for Windows to reinstall it because a test build implemented a restrictive security policy on that partition. Now I'm not seeing any option to boot into Arch at all. This is what fdisk -l shows from the live environment. /dev/sdb is a 128gb SATA SSD drive that is used solely for Windows. /dev/sda is a 1TB HDD that is partitioned with about 500gb for Windows and 500gb that Arch is on. How do I go about fixing this since there's no EFI partition on /dev/sdb now? I'd like to avoid having to completely redo the partitioning there (especially since it's been 4½ years since I did the installation initially). In the past I've used GRUB to handle things and I'd prefer to continue doing that. I'm thinking I messed something up when I was trying to fix the Windows bootloader last night after wiping its EFI partition.
https://imgur.com/a/EcGCJrt

cryptearth

Member

Registered: 2024-02-03

Posts: 1,223

Re: Lost ability to boot into Arch after Windows reinstall

please post text as text - not as image
as for get grub back:
depending on what you actually did either efibootmgr to deal with the entries will suffice or mount arch, chroot into and reinstall grub

Oldiesmann

Member

Registered: 2020-04-20

Posts: 17

Re: Lost ability to boot into Arch after Windows reinstall

Got it working sort of for now. I installed GRUB to the Windows EFI partition and then used os-prober with grub-mkconfig to find the Windows boot loader and add that to the boot menu. It's ugly but it works for now until I can properly fix it. The problem now is that /boot/efi doesn't point to anything and this will prevent grub-install from working in the future. I'll either have to remount /boot/efi to the Windows EFI partition or fix the /dev/sda1 partition and reinstall GRUB to that instead. Either way it's working now.

cryptearth

Member

Registered: 2024-02-03

Posts: 1,223

Re: Lost ability to boot into Arch after Windows reinstall

it depends on wether you use the ESP only for grub and its config - then /efi or /boot/efi will be the correct mountpoint - or if you store the kernel and initramfs along with grub then /boot is correct path

sidenote: as I recently learned /boot/efi seems to be not recommended
the wiki lists some sources and it all goes deep - for the sake of not argue about it I recommend read about it yourself and decide for your setup the best option - as: "it depends" (on your specific setup)