Recover broken bootloader

[lok...@gmail.com]

My laptop has started to fail to boot my 4.0rc2 installation. This started after doing a qubes-dom0-update, but I'm pretty sure that I had rebooted the machine successfully at least once since then.

The computer has now gone into a bootloop, and fails to display the GRUB screen. I can only assume that the bootloader is crashing. However, nothing is displayed on the screen.

Is there a recommended procedure to reinstall GRUB when booting from the installation media?

Regards,
Elias

[Marek Marczykowski-Górecki]

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Standard things should work:
1. Boot from installation media (rescue mode)
2. Agree to mount the system
3. Chroot into /mnt/sysimage (chroot /mnt/sysimage)
4. If /dev is empty, mount it with: mount -t devtmpfs none /dev
5. Execute: grub2-install /dev/sda (or other disk, depending on your
configuration)

Then, exit from chroot and reboot the system.

- --
Best Regards,
Marek Marczykowski-Górecki
Invisible Things Lab
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
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[barbud...@gmail.com]

Was having a similar problem. I have boot installed in a separate usb and after following the process of chroot... grub2 install and rebooting it ask me for the passphrase and all end up with a grub> shell with the system not booting. There is a way to clone my boot usb to another usb or to build a new one? or better reinstall. Thanks guys.

[barbud...@gmail.com]

>
> Was having a similar problem. I have boot installed in a separate usb and after following the process of chroot... grub2 install and rebooting it ask me for the passphrase and all end up with a grub> shell with the system not booting. There is a way to clone my boot usb to another usb or to build a new one? or better reinstall. Thanks guys.

Solved, was able to clone the boot usb before it broke definitely using:
dd if=boot.img of=/dev/sd(letter new boot USB) conv=notrunc

been boot.img the image of the old usb stick where I installed the boot partition when I installed Qubes. Without the conv=notrunc it didn't work, just if someone face a similar problem. Like I said in the previous message the chroot - grub-install process didn't work for me, maybe because I use FDE and been the boot partition in a separate USB.