Install and configure GRUB on USB key from Live CD

I had problem with my laptop, as it is a UEFI device.

Even if in the BIOS I've put the option "Legacy ..." for booting, I am able to boot the USB, then install Linux on a partition but not run it directly after the boot: writing GRUB on the MBR seems not to work. I guess there is some protection, or automatic recovery from Windows 10 going on.

Anyway, I decided to install the GRUB booter on a USB key, so that at least I can bypass this problem.

first mount the USB key (change sdb1 with your own, use fdisk -l or gparted)

> sudo mount /dev/sdb1 /mnt

then install grub on it

> sudo grub-install --no-floppy --root-directory=/mnt /dev/sdb

and then create a running configuration:

>  sudo grub-mkconfig -o /mnt/boot/grub/grub.cfg

Voila!