Intel SATA RAID (ICH5R)

[Aleksandar Milivojevic]

lee connell wrote:
> Hi all,
> 
> I have intel sata raid (ich5r).  I have it configured two 80gig drives 
> as a stripe.  I install fedora 3 perfectly fine with no problems, I let 
> fc3 format and partition the drives in which it chooses a logical 
> volume.  After installation is complete and i reboot, the system hangs 
> at a blank screen displaying "GRUB:"  i can't type at the prompt or 
> anything.  If i tell the bios not to use raid, it will boot-up fine, so 
> far i havn't checked again yet but it has hung on enabling swap, not 
> sure if it got past it yet or not.  Any suggestions?

RAID on ICH5R is marketing speach.  Technically, it doesn't have RAID. 
What it has is the ability to define *software* RAID inside the BIOS. 
Basically it is something that is possible with any chipset, it is all 
the BIOS thingy.  I'm suprised that no marketing guy came with the idea 
in pre-SATA days.  Special device driver is needed for this to work (and 
it will not be the ICH5R doing the RAID stuff, it will be the driver).

My guess is that if Microsoft hans't limited Windows 2000/XP software 
RAID support to server versions of their OS (yep, they simply turned off 
the feature in home/professional versions), we'd never see all those 
chipsets marketed as RAID capable (there wouldn't be a need for 3rd 
party software RAID device driver).

You have two options.  Both have advantages and disadvatanges.

Forget about "on-board fake RAID" support.  Turn it off in BIOS and use 
standard Linux software RAID.  Linux software RAID drivers are mature, 
and probably much more stable than any future (yeah, there's still none) 
driver that manufacturer of those "fake RAID" solutions could provide. 
Disadvantage of this solution is if you want to have Windows and Linux 
to share the RAID.

Another solution is using "on-board fake RAID" support.  I haven't done 
it, but you might have a look into devmapper.  Check out 
http://people.redhat.com/~heinzm/sw/dmraid/readme.  Supposedly, that way 
you can have Windows and Linux cooperate on what they see as RAID 
device.  I never tested it, and have no idea if it works at all.

-- 
Aleksandar Milivojevic <amilivojevic at pbl.ca>    Pollard Banknote Limited
Systems Administrator                           1499 Buffalo Place
Tel: (204) 474-2323 ext 276                     Winnipeg, MB  R3T 1L7