Unix & Linux
Dual boot ignores EFI devices
My pc does not boot anymore in EFI/UEFI mode. I had grub installed and was able to boot on both Windows 10 and Ubuntu Linux (14.04 LTS). I recently tried to install Fedora Workstation 29 'automatically' making space from the ubuntu partition. Since then I have not been able to boot in EFI/UEFI. The boot process simply do not see the hard drive as an EFI boot disk. I have tried to remove the Fedora installation, I installed a new version of ubuntu and nothing works. I have tried to reinstall windows, but I cannot boot from window flash drive. I can boot from linux flash drives, and from there I can see the disk partitions (even if I can't mount the Windows partition as it seems to be in hibernation state). Is there any possibility to restore the machine in working state? What am I supposed to do? I have tried asking for help here and here with scarse success.
EDIT: I've been able to boot the local ubuntu disk with Super Grub2 Disk. It actually gave me access to the grub rescue terminal. From there I was able to:
set root=(hd0,msdos1)
set prefix=(hd0,msdos1)/boot/grub
insmod normal
normal
this procedure gave me access to a set of bootable kernels, only the old ubuntu one is working. From ubuntu I mounted the windows partition
sudo mount -o remove_hiberfile /dev/sda4 /mnt/win
backup my windows and linux files.
Next step will be to format/reinstall Linux. From there I have to figure out how to reinstall Windows.
Solution
I would personally use a tool which will try to find and repair the boot partition. First boot on a live Ubuntu distro and install boot-repair:
sudo add-apt-repository ppa:yannubuntu/boot-repair
sudo apt update
sudo apt install boot-repair
And then execute and hopefully recover the previous state with success (this tool saved me once a couple of months ago):
boot-repair
Comments (3)
- +0 – Hello marc, thanks for your answer. I run the boot-repair on mt system, and here are the system diagnostics. I had no luck with this tool, I think my problem is somehow related to the fact that when I installed fedora the boot system was LVM (i.e. I messed up with things I do not understand properly). Now I cannot see my sata HD as a valid EFI device for booting. — Dec 29, 2018 at 10:22
- +0 – First to see if it is still there and avoid getting into specifics...did you tried
Super Grub2 Disklive distro? — Dec 29, 2018 at 14:50 - +0 – I can see the drives and also mount them if I boot from a live-usb (both fedora and ubuntu). I have tried grub2-install with no success. My problem is that on the boot the system does not see ant Uefi source/hd. — Dec 29, 2018 at 23:21
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