Re: what RAID levels does GRUB2 support?

[Wojciech Pyczak]

Dnia 2009-02-01, nie o godzinie 09:19 +0100, Felix Zielcke pisze: 
> Am Sonntag, den 01.02.2009, 01:48 +0000 schrieb Dave Abrahams:
> 
> > Sooo... 
> > 
> > * Will GRUB2 boot a linux system from RAID5 without a separate /boot 
> > partition?
> 
> This should work yes.
> 
> > * Has anyone posted a HOWTO about that?  
> > 
> > I tried and failed to configure such a system.  I wouldn't mind being the 
> > first
> > to write such a HOWTO if I could get some handholding from this group :-)
> 
> There shouldn't be anything special needed. Just make your RAID 5 and
> then do: grub-install "md0"
> in case /dev/md0 is your RAID5 and then GRUB2 gets installed onto every
> disk in the MBR.
> 

Yet another RAID related question, I decided to try out RAID partitions
(using grub svn versions), basically I've such disk layout:

md0: (RAID10 on 2 of 3 disks - /dev/sda1, /dev/sdb1)
   md0p1 - ext2, /boot
   md0p2 - reiserfs, /
   md0p3 - LVM2


Grub-mkconfig worked as expected detecting:

menuentry "GNU/Linux, linux 2.6.28.3" {
        insmod raid mdraid
        set root=(md0p1)
        linux   /vmlinux-2.6.28.3 root=/dev/md0p2 ro  
}


However grub-install /dev/(md0 | /dev/md0p1 | /dev/sda | /dev/sdb) throw
some errors(every time the same): 

grub-probe: error: no mapping exists for `md0p1'
Auto-detection of a filesystem module failed.
Please specify the module with the option `--modules' explicitly.

I tried using --modules="raid mdraid" but it didn't help much:

grub-probe: error: no mapping exists for `md0p1'
error: We don't support multiple metadata areas
Invalid device `md0'.
Try ``grub-setup --help'' for more information.


Error about multiple metadata is something which I reported here before
(related to LVM) but it doesn't really matter since grub isn't installed
at all (well, I suppose so at least). 

Is there any trick to make it work or is partitioned raid support still
work in progress ?