I have made a full disk clone of my encrypted S2 disk to an external USB disk with
dd if=/dev/nvme0n1 of=/dev/sdb status=progress
The S2 disk was not mounted when cloning, I used a live distribution on a USB stick.
When I reboot the computer boots from the USB drive. But when plugging the USB drive into other computers (I have tried 3) the drive is not bootable. I suspect the S2 disk is somehow used during the boot process?
How can I make the USB drive bootable?
I tried to make the first partition bootable with parted
parted set 1 boot on
but that did not help. Alos, fdisk
complained about "GPT PMBR size mismatch", but that seems to have been fixed by running parted
.
There are some other questions concerning disk cloning on Stack Exchange, but they don't seem to have the problem that the disk is not bootable at all.
EDIT: I have now tried cloning with Clonezilla, but get the same problem.
EDIT2: @njboot's comment make me suspect this problem is related to UEFI boot.
Best Answer
I made a little bit of progress on this, so here is a partial answer. I used this answer https://askubuntu.com/a/380564/210203.
In one of the partitions on the external drive, I copied
EFI/debian/grubx64.efi
toEFI/BOOT/bootx64.efi
. I also had to activate (hybrid) UEFI boot on the computers where I tried to boot from the backup.Both laptops now boot from the backup disk. They hanged at different places in the boot process though. I don't know if caused by missing drivers or perhaps getting access to the encrypted partition.
I may try later to physically remove the disk I am trying to backup and see if that computer boots from the backup.