Reading Disks from a Raid

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Hello all.

I am in desperate need of some help.
The situtation is basically this,
On took a project from a proceeding partner, looking at a NT 4 Server
with a raid config.
The OS has crashed leaving everything stuffed...

My issue is this: I do not know how this raid is configured, my
assumption (being a very dangerous word) is that it is RAID 1, there
are 4 disks all of equal value 4.3G SCSI Ultra Wide 2 68Pins.
I do not know in which order the disks are Mirrored (if mirrored) in

I need to get the company data off the disks. I dont care about the OS.

Is it possible for me to take out the one disk at a time, and plug it
into a PCI SCSI reader on another machine (WIN XPP) for the sake of
being able to read the information and getting off the data without
breaking the RAID Solution?

So really i wanna take each disk plug see whats on it, get what i need
and be able to save the RAID as is???

If I cant do this, is there any way I can read the information from any
of disks without rebuilding the OS or breaking the current RAID config?

If anyone could help it would be sooooo greatly app.!!!


Re: Reading Disks from a Raid wrote:

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Find the brand and model number info on the disk. If the disk has
a decent label sticker, all the necessary info may be on the label.

For a disk that is that old, it is possible there is a Write Protect
jumper on the drive. Install the Write Protect and move the
disk to the SCSI chain on another computer. Then, you should not have
anything to worry about, in terms of the meta data in the reserved
sector of the disk, getting munged. You should be able to image
the drive, and examine the four images from the comfort of your
desk. By imaging the drive, you have your backup copy, and have
less to worry about, in terms of losing the only copy you've got.
Remember to remove the Write Protect from all disks when you are
finished, so you don't accidently de-synchronize the array on
a subsequent boot.

The SCSI controller type used on the original machine, would
determine the location and format of meta data used to label
how the thing is RAIDed. I'm not aware of a wealth of data
suitable for reverse engineering stuff like that, so it may take
plenty of guessing along the way.

What would happen if you were to take the SCSI controller card
out of the original machine, and take the controller card and
four disks to a second machine ? Do you think in fact the
RAID array is unaffected by the OS crash, or is the suspicion
that the array has damage to the file structure ? In any case,
I would investigate the possibility of a Write Protect jumper
on each of the four drives, as that way nothing should happen
to the disks when you transplant them. I don't think Write
Protect is a "Windows friendly" feature, so if the disks are
also used to boot Windows, I would think Windows would freak.
I don't think Windows would boot on a write protected volume.

Doesn't your customer have backups ? I guess the data isn't
that important :-)


Re: Reading Disks from a Raid wrote:
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Most companies that do professional data recovery will also do RAID
arrays. If the disks are undamaged, this may be the best way to
proceed. I wouldn't mess. Or at least make  a clone of all the
individual disks, first.

Re: Reading Disks from a Raid

Perhaps add an inexpensive IDE/ATA/SATA drive to the dead machine while
the RAID Controller is unplugged and install Windows on this new drive.
  Then reboot w. RAID controller attached and let Windows discover the
new hardware.  Previous suggestion to image the drives, just in case, is
a good one.  I suspect that Windows will not boot/recognize a drive
properly if it is write-protected. wrote:
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Re: Reading Disks from a Raid

On 4 Jul 2006 06:31:06 -0700, wrote:

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Is the raid card separate or motherboard-integral?

If separate, place the card and all drives in the other
system just as they are now, OR, fix the actual problem-
repair or reinstall the OS.  Are these drives holding the OS
or a separate volume(s)?

It might not hurt to simply contact the prior admin and ask
about this array.

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You don't necessarily need to know, the first attempt should
be with that controller card and it will pick up the drives
as they are.  That is- the logical raid information has
nothing to do with the system or OS the drives are installed
in (in most cases, in theory NT could be set to do a
software raid but this is not at all likely, would be
outside of any reason).

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Do not do this.  Leave them all together for the time being.
"IF" these are members of RAID1 arrays, what you propose
could work, but it would be something to try last, not

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If a RAID1, each drive in the array would be complete, but
do you have some reason to believe it's RAID1 instead of
some other, like RAID5?

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No you don't wanna take each disk, that's the opposite of
the whole point of a raid array, that MULTIPLE drives are
bound together as fewer volumes.  Treat all drives and the
controller as a single entity.  If the controller is
integrated onto the motherboard, source a separate raid
controller of the same chipset, and try to match the RAID
bios revision too.

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Do not try to rebuild, break, or anything else.  Read the
data off, as a whole array.  That's all.

IF for some reason the data were not valuable and you did
know it was a RAID1, you could then try separately reading
each drive.  It is the least desirable thing, the drives are
meant to stay together to work and that is why they (are
together) are an array in the first place.

I don't mean to be insulting but are you sure you are the
one who should be handling this data salvage operation?  It
seems you lack a basic understanding of RAID arrays and
there might be someone better equipped to do this, even if
it meant an outside party (though we dont' know the value of
the data).

Frankly if the only problem is the operating system on the
server, it could be as easy to just fix that instead and
copy the data over the lan instead of moving all these
drives... unless of course, you were going to move them
anyway, to the destination system.

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