Homelab Hacker Blog Entry #0x10: GRUB command line

 https://askubuntu.com/questions/833006/how-can-i-manually-boot-windows-from-the-grub2-terminal

booting windows from GRUB prompt

GRUB> insmod ntfs

GRUB> set root=(hdX,gptX)

GRUB> chainloader (${root})/EFI/Microsoft/Boot/bootmgfw.efi

GRUB> boot

https://www.ubuntubuzz.com/2016/03/booting-gnulinux-manually-with-grub-prompt.html

booting ubuntu from GRUB prompt

GRUB> ls

GRUB> set root=(hd0,X)

GRUB> linux /boot/vmlinuz-4.2.0-16-generic root=/dev/sdb3

GRUB> initrd /boot/initrd.img-4.2.0-16-generic

GRUB> boot