Re: Cloning an XP installation to move from JBOD to RAID 0 Stripe

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Let's remember that JBOD means that all HDs are treated as a single, logical
volume, essentially "spanned". If you have two HDs in a JBOD array which
you intend to convert to RAID0 (stripped), then it's best to backup the JBOD
array to another HD, DVD/CD, whatever. You typically don't want to convert
spanned volumes directly to RAID0 since you can't be sure how the JBOD array
is populated (i.e., if any files actually span across the HDs), and how the
RAID controller will treat existing files. It's possible it wil destroy
everything across all HDs as part of initialization. At least I wouldn't
take the risk.

Remember also that I only provided a WARNING. What I recommend is TESTING
the current configuration w/ say, HDTach 3 (free for non-commerical use) so
you have a baseline for comparison! As I said, I found the problem w/
restoring images on *my* hardware, a Promise PCI RAID controller card. Each
RAID controller has its own BIOS/firmware and drivers, they may act very
differently across type and manufacturer. At this time, I'm only saying to
test it, before and after. Afterall, the whole point of using RAID0
(stripping) is to improve performance. If you don't realize the performance
increase, why bother and take the risk that comes from using RAID0
(remember, RAID0 increases the risk of data loss because failure of either
HD in the array typically means loss of ALL data).

If you find the array has NOT increased performance, is it better to do a
complete reinstall? Well, personally I wouldn't do it if I could avoid it.
There are ways to circumvent the problem, but I have to admit, it can get
rather complicated. In my case, I created a FAT32 partition and installed
MS-DOS 7.0 (part of Win98, and available from www.bootdisk.com) and made it
bootable (as C:). I then restored my XP from image copy to another FAT32
partition as D: (luckily XP was in FAT32 format, not NTFS, or else MS-DOS
7.0 would not have recognized it). I then booted MS-DOS 7.0 and did an
XCOPY from D: to C: (thus I was able to run the file through the RAID0
array!). Finally, I did an XP repair install on C: so it would boot XP, not
MS-DOS 7.0.

Yeah, kind of compicated, and not workable for all cases, but depending on
circumstances, it's possible to make it happen. But again, it may all be a
moot issue if you don't have the hardware problems I found. You may be
perfectly ok, all I'm suggesting at this point is, CHECK. Get before and
after results so you can be sure this effort isn't in vain. Worry about
rectifying the situation later, should you experience the same problems as
me.

Jim



"sauvagii" <sauvagii@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:E1F30BBA-34D5-41AF-A9F2-D06E7BCE86C4@xxxxxxxxxxxxxxxx
> Ok - the drives are connected to a Silicon image RAID controller on the
> motherboard (board is A8n SLI Deluxe from ASUS).
>
> Disks at the moment are set up in the SI setup (upon boot) as JBOD.
>
> So, by cloning and restoring to the array i'd get no benefit at all,
unless
> I did a full reinstallation?
>
> I'd be better in that case trying to install from scratch then, wouldnt I?
>
> Thing is, i've tried before (this pc has just been returned as it was sent
> back with a perceived MB fault, as the setup BSOD'd after setup, when the
> raid controllers were enabled, and the drivers installed during setup).
Can
> installXP normally if i dont enable the RAID features.
>
> Its been returned with "no hardware fault" - so im reluctant to blitz it
and
> start again.
>
> "Jim" wrote:
>
> > A word of caution here. When using a stripped array, I've noted
something
> > w/ my Promise FastTrak 100 TX2 that *might* be common to RAID hardware
> > generally.
> >
> > First time I setup a RAID0 array, I made an image copy of the source HD.
> > Then setup the array and restored the image to the array. BUT, there
was a
> > problem. A benchmark of the RAID0 array showed NO IMPROVEMENT! I was
> > initally puzzled, how could this be. I can't prove it, but what I
suspect
> > is that when you restore the image, it's typically based on sectors, not
> > files. When this happens, the RAID0 array is NOT optimzed across both
> > drives. Instead, it's mapped to ONE drive! IOW, all the benefits of
the
> > stripped array are lost. So I did a further test to prove (to my
> > satisfaction) my suspicions. I restored the image file to another HD
> > (external, slave, whatever). I then created an empty partition on the
new
> > array, then COPIED FILE BY FILE from the other HD to the new partition
on
> > RAID0, then ran a benchmark. Whalla, I ended up with vastly improved
> > performance.
> >
> > My conclusing was that although I could restore to the array directly
from
> > an image, it was self-defeating. Only by forcing files into the array
> > file-by-file did the array optimize storage across all HDs.
> >
> > So just a warning. Maybe my situation was unique to my hardware, but
this
> > was something I discovered quite some time ago and worked through a
> > solution. Benchmark that RAID0 array after the image is restored to it
to
> > make SURE you don't have the same problem.
> >
> > Jim
> >
> >
> >
> >
> > "Shenan Stanley" <newshelper@xxxxxxxxx> wrote in message
> > news:e6xV6KN8FHA.1276@xxxxxxxxxxxxxxxxxxxxxxx
> > > sauvagii wrote:
> > > > Can anybody tell me, if its possible using a third party
> > > > application such as Ghost, or Driveimage, to take the existing
> > > > installation on my PC (was only delivered yesterday) from a hard
> > > > disk and back up onto a spare disk - and then restore it to a newly
> > > > formatted/setup Raid 0 array (the installation already has RAID
> > > > drivers installed) - except the array has not been set up as i'd
> > > > asked.
> > >
> > > Hardware RAID - yes.
> > > Software RAID - unlikely.
> > >
> > > --
> > > Shenan Stanley
> > > MS-MVP
> > > --
> > > How To Ask Questions The Smart Way
> > > http://www.catb.org/~esr/faqs/smart-questions.html
> > >
> > >
> >
> >
> >


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