Arch Linux

tridentsk

Member

Registered: 2017-12-09

Posts: 1

[SOLVED]GRUB finds Windows EFI but does not show a bootmenu option

#2 did the trick for me!
Hi,
I'm dual booting Win10 and Arch on UEFI+GPT

fdisk output:

Disk /dev/sda: 465.8 GiB, 500107862016 bytes, 976773168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: F1F44F79-9974-459F-B22F-1AAF58FD1A8F

Device         Start       End   Sectors   Size Type
/dev/sda1       2048   1023999   1021952   499M Windows recovery environm
/dev/sda2    1024000   1228799    204800   100M EFI System
/dev/sda3    1228800   1261567     32768    16M Microsoft reserved
/dev/sda4    1261568 203778047 202516480  96.6G Microsoft basic data
/dev/sda5  203778048 512002047 308224000   147G Linux filesystem
/dev/sda7  512002048 976773119 464771072 221.6G Microsoft basic data

The EFI partition does not have an entry in my fstab, is it required?

How I installed grub - mounted sda5 to /mnt, sda2 to /mnt/boot and ran grub-mkconfig, detected linux images but not windows.

Finished installation and ran os-prober, output:

/dev/sda2@/EFI/Microsoft/Boot/bootmgfw.efi:Windows Boot Manager:Windows:efi

Ran grub-mkconfig -o /boot/grub/grub.cfg

Generating grub configuration file ...
Found linux image: /boot/vmlinuz-linux
Found initrd image(s) in /boot: initramfs-linux.img
Found fallback initrd image(s) in /boot: initramfs-linux-fallback.img
Found Windows Boot Manager on /dev/sda2@/EFI/Microsoft/Boot/bootmgfw.efi

checked grub.cfg for os-prober entry

### BEGIN /etc/grub.d/30_os-prober ###
menuentry 'Windows Boot Manager (on /dev/sda2)' --class windows --class os $menuentry_id_option 'osprober-efi-AE99-0866' {
	insmod part_gpt
	insmod fat
	set root='hd0,gpt2'
	if [ x$feature_platform_search_hint = xy ]; then
	  search --no-floppy --fs-uuid --set=root --hint-bios=hd0,gpt2 --hint-efi=hd0,gpt2 --hint-baremetal=ahci0,gpt2  AE99-0866
	else
	  search --no-floppy --fs-uuid --set=root AE99-0866
	fi
	chainloader /EFI/Microsoft/Boot/bootmgfw.efi
}
### END /etc/grub.d/30_os-prober ###

AE99-0866 is the UUID of dev/sda2 found with blkid, so that matches

On rebooting, GRUB only shows 'Arch Linux' and 'Advanced options for Arch Linux'.
What am I doing wrong?
Thank you.

Last edited by tridentsk (2017-12-16 02:04:12)

marakasmalan

Member

Registered: 2017-05-02

Posts: 15

Re: [SOLVED]GRUB finds Windows EFI but does not show a bootmenu option

I may not be the best one to answer your question, but it is been a while and you had no answer.

If I recall correctly, during installation and while chrooted, I followed the Installation wiki.

When I got to the bootloader section I has some difficulties as I was using f2fs and grub did not support it.

Systemd-boot did not automatically detect Linux kernels, but it did automatically detect the windows loader (bootmgfw.efi, I believe). I had to make custom entries for the linux kernels and tools such as MemTest86+:

$ pacman -S efibootmgr efitools
$ bootctl --path=/boot install

Then I had to edit:

$ vi /boot/loader/loader.conf
### existing file content
default arch
timeout 3
editor  0

I then had to add the boot entry for the linux kernel. I installed intel microcode updater to load before the initramfs (recommended, Arch wiki: Microcode)

$ pacman -S intel-ucode
$ blkid
# lsblk -f should also work
# get the PARTUUID for the drive where arch is installed
$ vi /boot/loader/entries/arch.conf
### existing file content
title   Arch
linux   /vmlinuz-linux
initrd  /intel-ucode.img
initrd  /initramfs-linux.img
options root=PARTUUID=[i]the PARTUUID you where observed with blkid[/i] rw 

If you do not require to sign the items to be compatible with SecureBoot Keys, the above should get you on your way.

Head_on_a_Stick

Member

From: The Wirral

Registered: 2014-02-20

Posts: 9,003

Website

Re: [SOLVED]GRUB finds Windows EFI but does not show a bootmenu option

How I installed grub - mounted sda5 to /mnt, sda2 to /mnt/boot and ran grub-mkconfig, detected linux images but not windows.

I think you forgot to `arch-chroot`

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Jin, Jîyan, Azadî