mjhjmtu

I have a xubuntu partition on my actual laptop with MBR and grub for dual boot windows and Linux.
I'm trying to clone the xubuntu partition and restore into a new laptop that is UEFI based.

In the new laptop ( HP Probook that originally had only windows 10 ) I managed to create an ext4 partition and to install a fresh copy of xubuntu.
Now I'm trying to overwrite the new ext4 partition with my xubuntu clonezilla image but I have problems after restore because xubuntu system won't boot and grub starts in cmdline mode.

I still can boot into windows partition through BIOS boot option.

This is what I've done:

1. Cloned the old ext4 xubuntu partition with clonezilla to image ( on USB disk )




2. On the new laptop I have disabled secure boot and disable legacy support in order to create/resize partitions




3. Created a new empty ext4 partition where I've installed a new xubuntu system. Now I can boot both windows and xubuntu




4. Restored the clonezilla xubuntu image on ext4 partition, overwriting the fresh install of xubuntu




5. The system is not able to boot with the xubuntu partition, starts with grub command line

How can I recover grub options?

thanks

Xubuntu's GRUB probably identifies the partition that contains the GRUB configuration file and/or the Xubuntu root filesystem by a filesystem UUID. When you overwrite the fresh install with a clonezilla image, this UUID gets overwritten by the filesystem UUID in the image.

GRUB command line mode indicates GRUB is not even finding its own configuration file and/or normal.mod file because of the changed UUID. It might be possible to use the command line mode to execute the necessary commands to boot manually, but that's quite tricky if you haven't used GRUB command line before. Instead, you should probably use Xubuntu Live CD Recovery - it's easier. To gain access to your installation, find the "Update Failure" paragraph and perform steps 1-7:

1.) Boot the [X]Ubuntu Live CD.

2.) Press Ctrl-Alt-F1

3.) sudo mount /dev/sda1 /mnt ## replace sda1 with actual device name of your root partition

4.) sudo mount --bind /dev /mnt/dev

5.) sudo mount --bind /proc /mnt/proc

6.) sudo mount --bind /sys /mnt/sys

7.) sudo chroot /mnt

Now you should be accessing the filesystem restored from the image, in command line mode.

But since your image was from a MBR-based system, it will most likely contain a MBR version of the GRUB bootloader. On your new system, you'll need the UEFI version of GRUB, and also the efibootmgr command. Before replacing GRUB, you might need to mount your ESP partition (= the small FAT partition that contains all the UEFI bootloaders of any operating systems on your disk.) to /boot/efi - if that mount point does not already exist, create it.

If the Live CD managed to start a network connection, you might now be able to just use apt commands:

sudo apt-get remove grub-pc
sudo apt-get install grub-efi-amd64 grub-efi-amd64-signed efibootmgr

It is quite likely that just installing grub-efi-amd64 will automatically rebuild your GRUB configuration as part of the GRUB re-installation process, and you won't need to do anything else. You may want to display the UEFI boot settings with sudo efibootmgr -v and compare it with the UEFI boot settings. You will be able to use the efibootmgr command to e.g. change the boot order from within Xubuntu.