NVIDIA RAID -- convert single drive to RAID w/o reinstalling?

[Rich Wales]

I have a WinXP (Home, SP2) system with an ABIT motherboard that
has NVIDIA RAID support.

I want to add another drive and convert the current C: drive (a
single, non-RAID disk) into a two-disk RAID 1 mirror array. Is
there any way to do this without losing my data and reinstalling
or ghosting the existing contents of my system?

Judging from the documentation, it looks like I might possibly
be able to convert the existing drive into a RAID 0 array (with
one disk), and then "morph" it into a two-disk RAID 1 array.
But it's not clear to me whether I can do that first step (i.e.,
convert a single, non-RAID disk into a one-disk RAID 0 array
without losing the existing data). Is this possible?

Rich Wales richw@richw.org http://www.richw.org

[Charles Howse]

Previously Rich Wales <richw@richw.org> wrote: I have a WinXP (Home, SP2) system with an ABIT motherboard that has NVIDIA RAID support.
I want to add another drive and convert the current C: drive (a single, non-RAID disk) into a two-disk RAID 1 mirror array. Is there any way to do this without losing my data and reinstalling or ghosting the existing contents of my system?
Judging from the documentation, it looks like I might possibly be able to convert the existing drive into a RAID 0 array (with one disk), and then "morph" it into a two-disk RAID 1 array. But it's not clear to me whether I can do that first step (i.e., convert a single, non-RAID disk into a one-disk RAID 0 array without losing the existing data). Is this possible?

Hi Rich,

usually what you want is not possible, since the RAID configuration
needs to be stored somewhere and there is no place the RAID
controller can be sure your OS has not in use. Therefore it needs
to hide at least one sector of the disks each from your OS.

However there may be another way (which I have used several
times, but with Linux softwware RAID):

1. Add your second disk.
2. Create a "degraded" (i.e. only one disk) RAID1 Array on the second disk.
3. Create a filesystem on the RAID1 array.
4. Copy files over.
Alternatively to 3.+4.:
3/4: Copy image over with imaging software that can resize a filesystem.
5. Remove the first disk and make sure your RAID1 array works as expected.
6. Add the first disk again and add to the RAID array. The Array will
sync, copying the contenst of the second disk to the first disk.

Note that until step 6. your original drive remains intact and
unchanged.

Important for this to work is that you have a second disk exactly the
size of the first disk or smaller or alternatively can tell the
controller that it shall not use more than a specific number of sectors
from the second disk. It is also important that you can create and
use a degraded array where only one disk is actually present.

Arno

[Rich Wales]

A few weeks ago, I asked how (if at all) I could convert a
single, non-RAID disk (my C: drive) into a two-disk RAID 1
mirror array, in a WinXP system using an ABIT motherboard
with NVIDIA RAID support.

As it turned out, I was able to do this without having to
do any major conversion of my original C: drive first. The
NVIDIA RAID system allows an existing non-RAID disk to be
handled by the RAID driver as a one-disk RAID 0 "array",
without having to clear or reformat the drive. After I did
that, I was then able to add a second disk (of equal or, in
my case, slightly larger size), and then convert the original
disk and the new disk into a two-disk RAID 1 array.

Note that when I went into the RAID management portion of
the BIOS and added my original C: drive to the RAID system,
I did =NOT= have the BIOS clear the drive!

I did this about two weeks ago, and it's been working fine.

I certainly can't guarantee that other RAID systems can do
this same slick trick -- redesignating a non-RAID drive as
a RAID 0 array without losing the data -- but, at the least,
NVIDIA can do it.

Rich Wales richw@richw.org http://www.richw.org

[Charles Howse]

Previously Rich Wales <richw@richw.org> wrote: A few weeks ago, I asked how (if at all) I could convert a single, non-RAID disk (my C: drive) into a two-disk RAID 1 mirror array, in a WinXP system using an ABIT motherboard with NVIDIA RAID support.
As it turned out, I was able to do this without having to do any major conversion of my original C: drive first. The NVIDIA RAID system allows an existing non-RAID disk to be handled by the RAID driver as a one-disk RAID 0 "array", without having to clear or reformat the drive. After I did that, I was then able to add a second disk (of equal or, in my case, slightly larger size), and then convert the original disk and the new disk into a two-disk RAID 1 array.
Note that when I went into the RAID management portion of the BIOS and added my original C: drive to the RAID system, I did =NOT= have the BIOS clear the drive!
I did this about two weeks ago, and it's been working fine.
I certainly can't guarantee that other RAID systems can do this same slick trick -- redesignating a non-RAID drive as a RAID 0 array without losing the data -- but, at the least, NVIDIA can do it.

Nice. I guess then thet NVIDIA stores the raid-configuration not on
the disk but instead e.g. in FLASH or a BIOS area. For a simple RAID
configuration you cannot move transparently to another machine that
would make sense.

Arno