F29, A reboot after a kernel upgrade put me at a grub prompt.

[CronoCloud]

Don't know what happened, did a dnf update on Tuesday, and after a reboot only had a grub prompt. And there was no emergency mode to boot to. Been trying to figure out what's wrong, and the XFCE spin I used to install (new computer), didn't have a rescue option. I'm thinking something happened and grub didn't properly update the config at the end of the update. I've got a UEFI system with 2 drives, 250 GB SSD (primary), and 2TB HDD (secondary)

[antikythera]

try reinstalling the bootloader as follows:

https://ask.fedoraproject.org/en/que...#post-id-40593

[CronoCloud]

try reinstalling the bootloader as follows:

https://ask.fedoraproject.org/en/que...#post-id-40593

Thanks! That pointed me in the general direction, but I needed a bit more trial and error after that to figure it out.

For me it was, booting into the live DVD, opening up a terminal, becoming root in that terminal and:

mkdir /mnt/sysimage
mount /dev/fedora/root /mnt/sysimage

All as the info says, but there's a secret sauce on newer systems, there's two boot related partitions, the regular "boot" and an "efi" directory that is technically part of boot, but is a separate FAT partition. As far as I can tell this is the default setup now. They both have to be mounted.

mount /dev/sda2 /mnt/sysimage/boot
mount /dev/sda1 /mnt/sysimage/boot/efi

mount --bind /dev /mnt/sysimage/dev
mount --bind /proc /mnt/sysimage/proc
mount --bind /sys /mnt/sysimage/sys

chroot /mnt/sysimage

grub2-install --target=i386-pc --force /dev/sda

But the second part of the secret sauce that makes it work is:

grub2-mkconfig -o /boot/efi/EFI/fedora/grub.cfg

In fact, I might have not needed to run grub2-install at all, just grub2-mkconfig pointing at the RIGHT directory.

I had to boot back into the previous kernal and then run a dnf --refresh update.

Anyway, it's back to normal. Thanks again.