mount grub recovery

To run a command as administrator (user "root"), use "sudo <command>".
See "man sudo_root" for details.

ubuntu@ubuntu:~$ sudo passwd
Введите новый пароль UNIX:
Повторите ввод нового пароля UNIX:
passwd: пароль успешно обновлён
ubuntu@ubuntu:~$ su
Пароль:
root@ubuntu:/home/ubuntu# cd
root@ubuntu:~# mount /dev/sda1 /mnt
root@ubuntu:~# mount -t proc none /mnt/proc
root@ubuntu:~# mount -o bind /dev /mnt/dev
root@ubuntu:~# mount /dev/sda5 /mnt/usr
root@ubuntu:~# chroot /mnt
root@ubuntu:/# grub-install /dev/sda
/usr/sbin/grub-probe: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
/usr/sbin/grub-probe: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
/usr/sbin/grub-probe: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
/usr/sbin/grub-probe: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
/usr/sbin/grub-setup: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
/usr/sbin/grub-setup: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
/usr/sbin/grub-setup: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
/usr/sbin/grub-setup: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
Installation finished. No error reported.
root@ubuntu:/# update-grub
Generating grub.cfg ...
/usr/sbin/grub-probe: warn: Discarding improperly nested partition (/dev/sda,msdos2,msdos1).
/usr/sbin/grub-probe: warn: Discarding improperly nested partition (/dev/sda,msdos2,msdos1).
/usr/sbin/grub-probe: warn: Discarding improperly nested partition (/dev/sda,msdos2,msdos1).
/usr/sbin/grub-probe: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
/usr/sbin/grub-probe: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
/usr/sbin/grub-probe: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
/usr/sbin/grub-probe: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
/usr/sbin/grub-probe: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
Found linux image: /boot/vmlinuz-2.6.35-22-generic-pae
Found initrd image: /boot/initrd.img-2.6.35-22-generic-pae
/usr/sbin/grub-probe: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
/usr/sbin/grub-probe: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
/usr/sbin/grub-probe: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
/usr/sbin/grub-probe: warn: Discarding improperly nested partition (hd0,msdos2,msdos1).
Found memtest86+ image: /boot/memtest86+.bin
Cannot find list of partitions!
done
root@ubuntu:/#