ubuntu@ubuntu:~$ sudo apt-get install grub2
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package grub2 is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
However the following packages replace it:
  grub-pc-bin grub-pc grub-ieee1275-bin grub-ieee1275 grub-efi-ia32-bin
  grub-efi-ia32 grub-efi-amd64 grub-efi-amd64-bin

E: Package 'grub2' has no installation candidate