UEFI goes to Grub Rescue, but MBR boots fine?

Did a restore from Timeshift a few weeks back, not sure on details. When it came back UEFI gave me a Grub Rescue.

… as usual:
very, very terse description - expecting us to elicit relevant information from you
to even learn what your problem might be
in order to then render advise

use … more … words :man_shrugging:

Sorry, not sure how to find out more, just if I select UEFI, it just goes to Grub Rescue, no error. Just not sure what to type.

UEFI goes to Grub Rescue, but MBR boota fine?

if MBR boots fine

why would you want to boot via UEFI - and expect it to work as well?

why disregard what works?
and focus on something that isn’t … ?

it’s a mystery to me …

If the Legacy MBR Boot mode works, but your UEFI boot mode gives you a Grub rescue prompt, it just means your grub.cfg in your ESP is wrong…
(Maybe the config in /boot/grub also)

Try to boot via a LIVE-ISO in UEFI mode and re-install your Grub (efi version).

I have the error it said “grub_debug_malloc” not found. Didn’t try the live boot yet.

MBR uses - well - MBR partition layout
EFI uses GPT partition layout

So while you cannot have MBR and GPT on the same disk,
you can have BIOS and EFI on the same GPT disk layout.

When GPT is the disk layout and you want to support both boot paradigms you need

  • unformatted partition min size 1M - partitition type EF02 (bios boot) - bios boot loader
  • fat32 formatted partition (calamares default to 300M) - partition type EF00 (efi boot) - efi boot loader
  • root partition - any size - partition type 8304 (Linux x86-64 root /)
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Just odd after a timeshift restore this happened, just wondering why? Linux is the only OS ib that drive.

How many drives do you have, you might be booting from another drive without you realizing it…:thinking:

Some system info about your drives/partitions would be handy, but as no technical info is provided at all, all we can do is guess…

I have 2 drives.
Widows- https://photos.google.com/search/_tra_/photo/AF1QipPWy2i5g9AvGk5cavOVflyvoz1-2pe91eLZ84bC

Linux- https://photos.google.com/search/_tra_/photo/AF1QipP-6oet3xJt6aj_bh8g3Njp9OipXUXdVNiaJ1nQ

sudo fdisk -l


Excuse me if this sounds rude, but I know you’re not a newcomer, yet all your posts start this cryptic, and everyone has to ask you for the same information every time. Please see:

Expecially thed part that says

Regardless of your problem, always do the following:
Copy-paste the following:

inxi --admin --verbosity=7 --filter --width


Instead of pictures.

Sorry I’m an a55h0le, but someone has to say it.

Disk model: SHGS31-1000GS-2 
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: dos
Disk identifier: 0x79ebd583

Device     Boot      Start        End    Sectors   Size Id Type
/dev/sda1  *          2048  246647377  246645330 117.6G  7 HPFS/NTFS/exFAT
/dev/sda2        246648832  247711743    1062912   519M 27 Hidden NTFS WinRE
/dev/sda3        247713792  248815615    1101824   538M 27 Hidden NTFS WinRE
/dev/sda4        248815616 1953523711 1704708096 812.9G  5 Extended
/dev/sda5        248817664 1551216639 1302398976   621G  7 HPFS/NTFS/exFAT
/dev/sda6       1551218688 1953523711  402305024 191.8G  7 HPFS/NTFS/exFAT

Disk /dev/sdb: 931.51 GiB, 1000204886016 bytes, 1953525168 sectors
Disk model: WDC WD10EZEX-08W
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: E5802447-08C9-7C47-B1FD-F7758A25D427

Device          Start        End    Sectors   Size Type
/dev/sdb1        4096     618495     614400   300M EFI System
/dev/sdb2      618496 1935065125 1934446630 922.4G Linux filesystem
/dev/sdb3  1935065126 1953520064   18454939   8.8G Linux swap

Partition 3 does not start on physical sector boundary.

Disk /dev/sdc: 1.89 GiB, 2031091712 bytes, 3966976 sectors
Disk model: DataTraveler 2.0
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0xe040036d

Device     Boot Start     End Sectors  Size Id Type
/dev/sdc1  *       63 3966939 3966877  1.9G  7 HPFS/NTFS/exFAT

SDC is just a blank thumb drive.

You have one disk BIOS/MBR - your Windows disk

You have one disk EFI - your Linux disk

You need to use your firmware boot override to be able to select which one to boot.

Bootloader for MBR and GPT cannot coexist - this is likely the cause of your issues.

Ok, I will change to EFI when I upgrade to 11 to fix it.

  1. Both links to your images give errors…

  2. Next time please post all info without cuting out parts…
    Fe. your windows disk total size… is most likely >=2TB, yet the model shows as a 1TB drive when searched on internet.
    (Correction i just noticed sda4 is an extended partition…)

You should be able to disable Legacy (BIOS-MBR) boot in your UEFI-BIOS, but we won’t be able to assist because only you know your hardware info…