grub problem

[Luca Ferrari]

On Thursday 21 May 2009 07:19:57 pm Rashkae wrote:
> Luca Ferrari wrote:
> > No way. I've tried doing the above, my partitions are /dev/cciss/c0d0p2
> > and /dev/cciss/c0d1p2, the second primary partition of both disks. I've
> > tried to change the partition type from raid to 83 (linux) and did again
> > the grub setup, but at the boot time the computer waits a lot and then
> > drop me to a busybox shell. I can see a message that states that /dev/md0
> > cannot be found (it is the root filesystem). I've got a boot filesystem
> > on both disk partitions, maybe grub cannot load /dev/md0?
> >
> > Any clue?
> >
> > Luca
>
> Umm, yeah, you broke your raid.  Grub is now booting just fine, but
> Linux is unable to find /md0, which is probably specified either as the
> root device in your menu.lst file, and/or in your /etc/fstab file... Not
> sure how I would even go about fixing this now.. though I suppose you
> could try changing the partition type back to Raid auto-detect.  If
> there were no other changes to disk that might just start working again,
> but it's a risky proposition.. I would start by backing up whatever data
> is still accessible on those drives before making any other changes.


No, the raid is fine. Let me explain: the root partition md0 is another 
partition on which md7 (/boot = /dev/cciss/c0d0p2 + c0d1p2) mounts.
If I start with a live cd and use my root partition md0 it works and I can see 
all my data. Also md7 was working before I changed the paritition type. I 
guess data in partitions is still there, and fine, but grub does not know where 
to install and how to load.
Having the two boot partitions ready, and having done the setup on them, how 
can I instrument grub to load my system from there?

Luca