In Linux you could face an impossibility to mount a crypted partition.
The command that could be useful then are
1. sudo dmsetup ls --tree
2. ls -l /dev/mapper/
3. sudo dmsetup remove /dev/dm-0
You have to replace dm-0 with your result in 2.grub rescue
It could happen that your PC, after some operations (i.g. with gdisk) doesn’t start booting and you are therefore in grub rescue prompt. A very unpleasant situation.
The steps to follow are:
- see what are the partitions, with the command
ls- you should see something like:
(hd0)(hd0,msdos1)(hd0,msdos2)(hd1)(hd1,gpt1)
- you should see something like:
- understand what is the right partition to boot (i.g. hd0,gpt2):
- you can list a single partition to see what it contains, with the command ls (hd0,gpt2). You should be able to see if a partition is the right one.
- give the command
set prefix=(hd0,gpt2)/boot/grub - give the command
set root=(hd0,gpt2)/ root=/dev/sda2(if the right partition is hd0,gpt2 the name is /dev/sda2, if it was hd1,gpt3 it would be /dev/sdb3) - give the command
insmod normal - give the command:
normal(orboot)
In this way the system should start with the expected partition.
boot useful tips
- It is not necessary to start booting with EFI if you have GPT partitions (you could choose to have legacy boot with GPT partitions).
- It is not necessary that EFI partition be at the start of a disk: it could be in every place, provided that it has a) boot (esp) flags, and b) at least 110mb of space.