Thanks for your reply.
What the OROM says is that both of my volumes are bootable. 
/dev/md126 corresponds to Volume0, and its first partition (ext4) has the boot 
flag set.
My problem is that I cannot get grub2 installed on the device at all. I did 
try, as you suggested, to set
(hd0) /dev/md126
in the file and then issue
> grub-install --modules=raid /dev/md126
but I still get the same error message(s):
grub-probe: error: no mapping exists for 'md126'
grub-setup: error: no mapping exists for 'md126'
What is interesting is that, at the grub shell, I can do
grub> probe -l (hd0,1)
it returns "OS" which is the label I set for it, so the device can, under 
certain circumstances, definitely be detected. Nevertheless, grub-install does 
not seem to behave the same way.

--- On Sun, 12/27/09, Michael Evans <> wrote:

From: Michael Evans <>
Subject: Re: grub-setup: error: no mapping exists for ... in GRUB2 v1.97.1 on 
fake (IMSM) RAID
To: "Lapohos Tibor" <>
Date: Sunday, December 27, 2009, 7:26 PM

On Sat, Dec 26, 2009 at 5:33 AM, Lapohos Tibor <> wrote:

Hello All,
I have 2 SATA disks in an Intel Matrix RAID setup. It contains two volumes, one 
in RAID1, the other in RAID0 configuration. These I created using the Option 
ROM of the motherboard,  partitioned using cfdisk, and finally assembled into 
RAID devices using mdadm v3.0.3. As such, I obtained the following devices:
/dev/md127 (the container to which /dev/md/imsm0 is pointing)
/dev/md126 (the RAID1 "Volume0" pointed at by /dev/md/Volume0)
/dev/md126p1 (the first partition intended to serve as the root fs)
/dev/md126p2 (intended for user space)
/dev/md126p3 (intended for swap)
/dev/md125 (the RAID0 "Volume1" pointed at by /dev/md/Volume1)
/dev/md125p1 (intended for user scratch space)
/dev/md125p2 (itended for swap)
(the long names came from mdadm v 3.0.3).
If I boot from my USB memory stick, and make a stop at the grub shell, I can 
see all these partitions listed as (hd1) (hd1,[123]), (hd2) and (hd2,[12]), 
while my USB stick comes up under (hd0) and (hd0,[12]). Therefore, I would dare 
to say that grub does detect these devices.
I tried to install grub 1.97.1 on /dev/md126 by countless ways without success. 
The command
$ grub-install --modules=raid /dev/md126 
for example returns the error message
$ grub-setup: error: no mapping exists for "md126"
The /boot/grub folder got created correctly, but the "" file does not 
mention any virtual RAID devices. It reads:
(hd0) /dev/sda (SATA1)
(hd1) /dev/sdb (SATA2)
(hd2) /dev/sdc (USB flash memory stick)
which, by the way, does not resemble what the 
sh: grub> ls
command returns before booting (see the list described before).
Do I need to give up using "fake RAID" and turn to pure SW RAID to get the 
system up and running, or is there a way to install GRUB2 in this configuration?
Your help is much appreciated. Thanks ahead,
Help-grub mailing list

If you -know- that given drives will be in some positions during startup then 
you can edit the file your self to tell grub where things will be on 

You should only provide the containers; however a very important question 
exists.  Are you able to select one of those containers as your boot volume 
within the bios?  If so make it like that and tell grub that the volume is 
'hd0' instead of /dev/sda.  Then you can do the usual setup/install and it 
should work when using that

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