Re: [gentoo-user] How to get raid

[Jeff Cranmer]

On Wed, 2012-01-04 at 14:39 +0100, Volker Armin Hemmann wrote:
> Am Dienstag, 3. Januar 2012, 21:57:18 schrieb Jeff Cranmer:
> > Hi all,
> >
> > I have recently built a new system, running Gentoo on a Sabertooth 990FX
> > motherboard.  The board has a raid controller on which I'm running a
> > 120GB solid state drive for the OS (Raid 0) and a set of three 1.5TB
> > drives which were previously running as a RAID5 array.
>
> no, it does not have a raid controller. It is bios raid. AKA fake raid. You
> will have less trouble if you stop using it.
>
> google for mdadm. There are some very nice howto's.
>

Not sure I'd agree with you about the howtos being nice.  They mostly
deal with trying to boot from a RAID array (don't want that, as I have
my OS on a non-RAID 120GB SSD).  They're also contradictory, with some
saying I need dmraid, and some saying not.  Most seem to make no more
than a passing nod towards genkernel.

So, given that from the links that I've found, here's my starting set of
questions.

In /etc/genkernel.conf, which options do I need to enable.
One guide suggested the following settings 
DMRAID="no"
MDADM="yes"
MDADM_CONFIG="/etc/mdadm.conf"
MDADM_VER="3.1.4"

If this is correct, does it matter that my mdadm version which I emerged
is 3.1.5?  The tarball in /var/cache/genkernel/src is
mdadm-3.1.4.tar.bz2
Should I copy mdadm-3.1.5.tar.bz2 from /etc/portage/distfiles into there
and rebuild genkernel.

Do I need the dodmraid option compiled into genkernel, or is that only
for fakeraid, or situations where I need to boot from a raid partition?

Do I need the dodmraid option set true in the grub.conf file, or is
'domdadm' more appropriate?

Jeff