How to restore grub in UEFI mode

[real bas]

Hi, I recently upgrade my debian (UEFI) and grub is gone.. I try to recovery grub but failed or I`m doing something wrong.

This steps I following are:

-create usb with live cd

-change boot option to legacy mode and disable secure boot consequently

-boot from live cd (Here, when I boot from CD and check if i`m using EFI or legacy, always say legacy, maybe be here the problem)

-mount my partition / in /mnt

-install grub in /mnt

when install grub i receive the following message:

Installing for i386-pc platform.
grub-install: warning: this GPT partition label contains no BIOS Boot Partition; embedding won't be possible.
grub-install: warning: Embedding is not possible.  GRUB can only be installed in this setup by using blocklists.  However, blocklists are UNRELIABLE and their use is discouraged..
grub-install: error: will not proceed with blocklists.

Can someone help me?

[Rodolfo]

Hi,

-change boot option to legacy mode and disable secure boot consequently

I think in this part you do not need to turn to legacy, leave it UEFI, only disable secure boot.

Debian Jessie has support for UEFI boot.

Try reinstall grub using the normal installation cd, in it has an option to recover or access shell in your installed system.

[Rodolfo]

When i recovered my grup-efi, and i remember that i reinstalled it with apt-get, and automatically do the right configurations.

Do not use grub-install, reinstall the package and leave the configurations to it.

2016-01-05 15:31 GMT-04:00 real bas <real...@gmail.com>:

I leave it UEFI and only disable secure boot, when I use this command:
   [ -d /sys/firmware/efi ] && echo EFI || echo LEGACY

   return EFI normally

but when I use grub-install:
grub-install --root-directory=/mnt /dev/sda
say: grub-install: error: cannot find EFI directory

[real bas]

I leave it UEFI and only disable secure boot, when I use this command:
   [ -d /sys/firmware/efi ] && echo EFI || echo LEGACY

   return EFI normally

but when I use grub-install:
grub-install --root-directory=/mnt /dev/sda
say: grub-install: error: cannot find EFI directory

2016-01-05 19:00 GMT+00:00 Rodolfo <rof2...@gmail.com>:

[Rodolfo]

Well, than is diferent to me, I used only this steps that i told to you and it works.

Look these two links:

https://wiki.debian.org/GrubEFIReinstall

and

https://www.thomas-krenn.com/en/wiki/Restore_Ubuntu_UEFI_Boot_Entries_after_BIOS_Update

Maybe help you.

2016-01-05 15:40 GMT-04:00 real bas <real...@gmail.com>:

I try mount my partition /dev/sda9 in /boot/efi but say /boot/efi doesn't exist (no have efi directory in boot then I create it and mounted in /boot/efi)

then I reinstalled grub-efi and try grub-install /dev/sda but say:
error: /boot/efi doesn't look like an EFI partition

[real bas]

I try mount my partition /dev/sda9 in /boot/efi but say /boot/efi doesn't exist (no have efi directory in boot then I create it and mounted in /boot/efi)

then I reinstalled grub-efi and try grub-install /dev/sda but say:
error: /boot/efi doesn't look like an EFI partition

2016-01-05 19:34 GMT+00:00 Rodolfo <rof2...@gmail.com>:

[real bas]

I following this links but gets error to install grub like as my partition doesn't look like a EFI

[jdd]

Le 05/01/2016 20:40, real bas a écrit :

> error: /boot/efi doesn't look like an EFI partition

is it fat32?

jdd

[real bas]

Hi again,

I fix it after several hours, I followed what Rodolfo say about boot options (I noticed that liveCD or liveInst of debian doesn't do UEFI boot, only legacy boot) and use this answer [1] to complement (very explain) using ubuntu CD (with UEFI boot).

[1] http://superuser.com/a/376471

I hope it helps other users, thanks Rodolfo. 

[Steve McIntyre]

real...@gmail.com wrote:
>
>Hi, I recently upgrade my debian (UEFI) and grub is gone.. I try to
>recovery grub but failed or I`m doing something wrong.
>This steps I following are:
>-create usb with live cd
>-change boot option to legacy mode and disable secure boot consequently
>-boot from live cd (Here, when I boot from CD and check if i`m using EFI or
>legacy, always say legacy, maybe be here the problem)
>-mount my partition / in /mnt
>-install grub in /mnt

As you semi-identify, booting in legacy mode from a live cd is the
reason you're not getting anywhere. If you're wanting to re-install
grub-efi then you *must* be in UEFI mode to be able to do that. Our
live CDs unfortunately don't have UEFI support (long story), so your
best bet is to boot an installer CD/DVD/USB in rescue mode. Make sure
it's booted via UEFI - the boot splash screen should say so. From
rescue mode, you can re-install grub and that should fix your problem.

--
Steve McIntyre, Cambridge, UK. st...@einval.com
"Further comment on how I feel about IBM will appear once I've worked out
whether they're being malicious or incompetent. Capital letters are forecast."
Matthew Garrett, http://www.livejournal.com/users/mjg59/30675.html

[Rodolfo]

You are welcome =D.