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Dual Boot Fedora - GRUB issues, unknown device

asked 2017-10-25 14:40:06 -0600

NotAnAmbiTurner gravatar image

updated 2017-12-02 15:34:16 -0600

I may have made a mess when trying to make a dual-boot fedora installation. Plus side: Fedora works. Downside: Software updates don't seem to take, and I can't boot into Windows.

I have run grub2-mkconfig -o /boot/efi/EFI/fedora/grub.cfg, which seems to work, but I still get the following errors when booting (see images below). I think if I fix GRUB, things should start to work as expected. Unfortunately, I do not know how to do that. My fdisk -l looks like this:

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: E9B6217F-AA20-4DD1-B90E-C7A42FE118A2

Device         Start       End   Sectors   Size Type
/dev/sda1       2048   1230847   1228800   600M Windows recovery environment
/dev/sda2    1230848   1640447    409600   200M EFI System
/dev/sda3  725817344 727914495   2097152     1G Linux filesystem
/dev/sda4    2107392 725817343 723709952 345.1G Microsoft basic data
/dev/sda5  727914496 976773119 248858624 118.7G Linux LVM

Partition table entries are not in disk order.

Disk /dev/mapper/fedora-root: 50 GiB, 53687091200 bytes, 104857600 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

Disk /dev/mapper/fedora-swap: 3.9 GiB, 4156555264 bytes, 8118272 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

Disk /dev/mapper/fedora-home: 64.8 GiB, 69570920448 bytes, 135880704 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

And my Disk Manager looks like this:

I am not experienced in such things, and so have unfortunately no idea what I can add beyond what happens during boot, so I have put those screenshots below and I suppose just need to ask "help?".

I am using a Acer Aspire E 15 Start (ES1-512-P72R), which IIRC had some sort of hardware issue with Ubuntu (and maybe all linux installs), I could be very off on that. I do get occasional freezes on Fedora, and they happened quite frequently when Ubuntu was installed. I am using UEFI, though if I'm honest I no longer recall what that means / if that has any applicability to this issue.

It is initially trying to boot into GRUB, because when I select GRUB from the menu that lists GRUB and "unknown device" in Screenshot 2, I get put back to Screenshot 1. My boot, in order:

Screenshot 1

Screenshot 2

Screenshot 3

I would like to turn this back into a dual-boot computer. The first step is probably repairing GRUB. Any help would be appreciated.

Output of find /boot/efi -exec ls -ld {} + (thanks @villykruse):

drwx------.  5 root ...
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What files do you have in /boot/efi? Run

find /boot/efi -exec ls -ld {} +

and add the output to your question.

Is it possible to to make sure your pictures are in focus?

villykruse gravatar imagevillykruse ( 2017-10-26 02:26:18 -0600 )edit

@villykruse done, thank you. Sorry for the focus issues.

NotAnAmbiTurner gravatar imageNotAnAmbiTurner ( 2017-12-02 15:42:18 -0600 )edit

It looks like /EFI/Microsoft/Boot was wiped out during install of Fedora, probably because the efi file system was re-formatted. Maybe someone else knows how to restore these files.

villykruse gravatar imagevillykruse ( 2017-12-03 05:34:13 -0600 )edit

2 Answers

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answered 2017-10-25 15:43:32 -0600

sideburns gravatar image

Welcome to ask.fedora. You don't really boot into GRUB, you use it to decide which OS (and/or kernel) to boot into, which is probably why you get the errors you do when you select it. You have three kernels installed (the most recent and two older ones as backups) and a rescue kernel for emergencies, which is normal. I don't know anything about Acer computers, but you may be able to go into the boot manager and tell it to boot into the Unknown Device first, after which we can worry about your freezing issues. If you have trouble getting into that boot manager, talk to Acer support, and I'm sure they can talk you through it. Good luck, and please report back on how things go.

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Thanks for the answer. How does that help me boot into Windows? I can definitely boot into fedora, and selecting the right option isn't really much of a hassle. What I would really like to do is figure out how to repair GRUB so that dual-boot works properly.

NotAnAmbiTurner gravatar imageNotAnAmbiTurner ( 2017-10-26 01:57:00 -0600 )edit

Judging from your third screenshot, GRUB doesn't know that you have Windows. You can probably correct this by using os-prober but I've never used it myself. With luck, somebody else here can guide you.

sideburns gravatar imagesideburns ( 2017-10-26 02:11:09 -0600 )edit

So apparenttly I canet get into my BIOS. I did hit F12 / DEL alternatingly, and it gave me a book menu sans "unknown device," at which point I selected grub, got the error, went back to the menu that has GRUB and unknown device. os-prober has not solved this for me unfortunately... I get no output when I run sudo os-prober.

NotAnAmbiTurner gravatar imageNotAnAmbiTurner ( 2017-12-02 15:43:58 -0600 )edit

answered 2017-12-03 13:50:12 -0600

cmurf gravatar image

When Fedora is booted, if /boot/efi/EFI/Microsoft/Boot/bootmgfw.efi does not exist (that path requires root privilege) then the Windows bootloader has been stepped on and needs to be replaced. It's possible Windows install media can do a repair and replace it, that used to be true for BIOS/MBR installations, but I vaguely recall having to manually copy the bootloader files from a Windows 10 installer USB stick (or ISO mounted on loop) to the EFI system partition on UEFI/GPT systems.

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Thank you - does this also address the issue that GRUB is apparently not working, or is the GRUB issue something separate?

NotAnAmbiTurner gravatar imageNotAnAmbiTurner ( 2017-12-05 03:54:40 -0600 )edit

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Asked: 2017-10-25 14:40:06 -0600

Seen: 674 times

Last updated: Dec 03 '17