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When booting via grub I get the following error:

error: unknown filesystem.
grub rescue> ls
(hd0) (hd0,msdos7) (hd0,msdos6) (hd0,msdos5) (hd0,msdos1) (fd0)
grub resuce> set

If I change the root and prefix to hd0,msdos6 I can boot successfully. Except grub encounters the same error when I reboot. How can I get grub to remember these settings?

Potentially useful information:

  • I am using RAID0 and grub is installed to /dev/mapper/isw_fbifcgeic_RaidVolume0
  • In Linux (Ubuntu 11.10) my grub.cfg points to root at (hd2,msdos6)
  • grub-mkdevicemap -m - lists the /dev/mapper entry at hd2

Any help would be much appreciated! It's super annoying needing to rescue grub every time I boot my system.

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It turns out that my raid0 configuration was really a "fakeraid" configuration. It also turns out that there was a bug in grub-probe related to fakeraid. Once I ran sudo update grub-pc followed by grub-install /dev/mapper/isw_fbifcgeic_RaidVolume0 I could successfully boot my computer once more without manual intervention.

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