Arch Linux

MerrinX

Member

From: Norway

Registered: 2020-01-10

Posts: 6

Win10 bootmgr on same partition as grub [SOLVED]

I do not know where to put this, it have never happened before, but i re-installed Arch, then I installed win10 after. and Windows did not create a EFI boot partition when installed, tried twice. Instead when running os-prober, it says

/dev/nvme0n1p1@/EFI/Microsoft/Boot/bootmgfw.efi:Windows Boot Manager:Windows:efi

That is my boot/efi partition also, i created that when i installed Arch. Never seen this before. I was trying to find the Win EFI partition so I could mount it and duel boot, with having win10 in grub menu, but it was so confusing seeing this.
Is this something new, from windows side? How do i manage to get win in grub now, i cannot double mount same partition.

Any help would be much appreciated.

Last edited by MerrinX (2022-01-24 11:35:59)

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 25,097

Re: Win10 bootmgr on same partition as grub [SOLVED]

That is absolutely intended, perfectly safe and the way it should happen. Welcome to UEFI, where having multiple operating systems coexist is actually part of the spec and not an afterthought hack.

For generating the appropriate entry read https://wiki.archlinux.org/title/GRUB#D … ng_systems

MerrinX

Member

From: Norway

Registered: 2020-01-10

Posts: 6

Re: Win10 bootmgr on same partition as grub [SOLVED]

Idiotic that i did not think of un commenting that myself, however this put me a tiny bit out, never seen windows do this.Always made its own boot partition before, maybe just luck from my side.
Thank you for helping me.

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 25,097

Re: Win10 bootmgr on same partition as grub [SOLVED]

If you install it first on the disk it will create the ESP itself and you'd be installing GRUB "on that". Having multiples here on a single disk is a waste of space - and depending on your mainboard - potentially actually not supported as it's generally assumed that there's "only one" per disk (they should actually support multiples but there are no guarantees when it comes to HW vendor UEFI implementations)

As for thinking on uncommenting that yourself, if you read the terminal output when running grub-mkconfig it should actually mention this.

If this is [SOLVED] please mark it as such by editing the title in your first post.