В системе было 3 своп раздела, два неактивных. Я взял и штатными средствами удалил эти разделы. После перезагрузки GRUB 2 перестал отображать список ОС (у меня их две - win 7 и Ubuntu 11.04).

Вот полезная информация:

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Boot Info Summary:

=> Grub 2 is installed in the MBR of /dev/sdb and looks at sector 217227160 of the same hard drive for core.img, but core.img can not be found at this location.

sdb2: ______________________________________________________________________

File system: ntfs
Boot sector type: Windows Vista/7
Boot sector info: No errors found in the Boot Parameter Block.
Operating System: Windows 7
Boot files/dirs: /bootmgr /Boot/BCD /Windows/System32/winload.exe /GRLDR

sdb3: ______________________________________________________________________

File system: Extended Partition
Boot sector type: Unknown
Boot sector info:

sdb5: ______________________________________________________________________

File system: ntfs
Boot sector type: Windows Vista/7
Boot sector info: According to the info in the boot sector, sdb5 starts at sector 4. But according to the info from fdisk, sdb5 starts at sector 186534404.
Operating System:
Boot files/dirs:

sdb6: ______________________________________________________________________

File system: ext4
Boot sector type: -
Boot sector info:
Operating System: Ubuntu 11.04
Boot files/dirs: /boot/grub/grub.cfg /etc/fstab /boot/grub/core.img

sdb7: ______________________________________________________________________

File system: swap
Boot sector type: -
Boot sector info:

Помогите восстановить GRUB 2, я пробовал это:

ubuntu@ubuntu:~$ sudo mount /dev/sdb6 /mnt
ubuntu@ubuntu:~$ sudo update-grub
/usr/sbin/grub-probe: error: cannot stat `aufs'.
ubuntu@ubuntu:~$ sudo grub-install /dev/sdb6
/usr/sbin/grub-probe: error: cannot stat `aufs'.
ubuntu@ubuntu:~$ sudo grub-install --recheck /dev/sdb6
/usr/sbin/grub-probe: error: cannot stat `aufs'.

и так:

root@ubuntu:/home/ubuntu# sudo grub-install --force --root-directory=/mnt /dev/sdb6
/usr/sbin/grub-setup: warn: Attempting to install GRUB to a partitionless disk or to a partition. This is a BAD idea..
/usr/sbin/grub-setup: warn: Embedding is not possible. GRUB can only be installed in this setup by using blocklists. However, blocklists are UNRELIABLE and their use is discouraged..
Installation finished. No error reported.

Ничего не помогло...