On Wed, Jan 9, 2019 at 12:16 PM Hans de Goede <hdegoede(a)redhat.com> wrote:
On 09-01-19 16:10, Richard Shaw wrote:
> On Wed, Jan 9, 2019 at 8:57 AM Hans de Goede <hdegoede(a)redhat.com
> I'll double check but it treats the USB has a hard disk and I don't
recall seeing a EFI option. The ONLY option related to EFI in the BIOS is
for CD/DVD devices which is set, hence Win10 getting installed EFI using
the disc. I may have to actually burn the ISO to disk to get it to boot in
In that case it is probably easier to convert your existing install to
1) Move /boot/efi contents to some place
2) Edit fstab mount the existing EFI system partition on /boot/efi
3) mount /boot/efi
4) move /boot/efi contents back in place
5) Run efibootmgr, doing something like:
efibootmgr -c -d /dev/sda -p 1 -L Fedora -l '\EFI\fedora\grubx64.efi'
This will tell your BIOS to add a "Fedora" entry to its UEFI boot menu.
You may need to adjust the /dev/sda and the partition "1" to match
your system. Also this assume your system and Fedora install are 64 bits,
UEFI is only supported with a 64 bit install. Perhaps that is why
your BIOS is not giving an EFI option for the USB disk ?
I've been 64 bits only for years...
For some more info on how to convert a system to UEFI see:
You may also want to use the -o option after running the -c
(for create) command to make Fedora the default.
Ugh I just realized that efibootmgr will only work if
you are already booted in UEFI mode. If you can get Windows
to boot again by trying to re-enable UEFI or some such
in the BIOS you can probably find a similar tool under
Windows. Sometimes UEFI BIOS also allow you to select an
EFI binary to execute, in that case you can navigate to
EFI\fedora\grubx64.efi and execute it directly or if
you can start an EFI commandline shell you can start
grubx64.efi from there.
Worst case I can hopefully boot UEFI from the Live disc (instead of USB),
move all the data around, and then chroot before running efibootmgr.
Once you've booted Fedora in UEFI mode that way you can
use the efibootmgr command to permanently add Fedora to
the list of OS-es the UEFI part of your BIOS knows about.
If there is none of these options you may need to clear your mbr
or open fdisk and re-write the existing GPT table, so that you get
a dummy old style partition table (as is normally used with GPT)
that may kick the BIOS back into UEFI mode and give you Windows 10
Note steps 1-4 are harmless (if done correct) and you will still
be able to boot in legacy mode regardless.
We'll see what happens. I've recovered from worse and my son doesn't have
any critical data anyway.
Thanks for the help!