Bulk erased drives
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From: AZ Nomad on 24 Jun 2010 13:34 On Thu, 24 Jun 2010 17:02:31 GMT, Nico Coesel <nico(a)puntnl.niks> wrote: >AZ Nomad <aznomad.3(a)PremoveOBthisOX.COM> wrote: >>On Wed, 23 Jun 2010 19:19:02 -0700, D Yuniskis <not.going.to.be(a)seen.com> wrote: >>>Hi, >> >>>A 501(3)c that I am affiliated with received a donation >>>of several hundred ~80G SATA/PATA drives the other day. >>>They have allegedly (?) been bulk erased. I was asked, >>>today, if there is any way to make the drives serviceable, >>>again. >> >>>I have not seen the drives or had a chance to play with >>>any of them. As "proof" that they were bulk erased, I >>>am told each drive bears a label: >>> ERASED >>> Magnetic data is completely erased. >>> Erased product can't be reused or repaired. >> >>>When *I* take a drive out of service, I "bulk erase" them >>>(after "electronically" overwriting the existing data) and >>>then subject them to the 500G drop test :> But, I'll admit >>>I have never *tried* to recover data from a drive thusly >>>(ahem) "treated". >> >>>My initial response to them was "recycle them, they're trash". >>>Was I too hasty? >> >>>I would imagine all the servo information, low level >>>formatting, bad sector table, etc. are gone or corrupted >>>so putting these back into service would require "special >>>factory tools"... >> >>An external magnetic field will physically damage the drive before it >>starts to erase the data. The gap between platter and case is enough >>to make external bulk eraseing nearly impossible. They probably just >>ran software to erase the drives. >I agree. That would be the easiest thing to do and still erase the >data beyond recovery. I once worked at a department of defence shop and the easiest way to wipe drives was to sand off the media. :-) We actually had some failed drives returned for warranty replacement that had received such treatment.
From: Vladimir Vassilevsky on 24 Jun 2010 13:45 AZ Nomad wrote: > I once worked at a department of defence shop and the easiest way to wipe drives > was to sand off the media. :-) I use old HDDs as targets at the firing range. Vladimir Vassilevsky DSP and Mixed Signal Design Consultant http://www.abvolt.com
From: Nobody on 24 Jun 2010 16:56 On Thu, 24 Jun 2010 10:00:27 -0500, AZ Nomad wrote: >>Depending upon the field strength, it may have demagnetised the magnets in >>the voice coil and/or motor, or even caused physical damage via forces on >>ferrous parts. > > You're joking, right? Have you seen how powerful the magnets used for > hard drive positioners are? You'd need a device capable of lifting > a dumptruck even to begin to affect one of those magnets. It's the flux density that counts, not the total flux. I don't know what the numbers are for a purpose-built bulk eraser, but I've encountered drive motors where the magnets were no longer magnetic (or, at least, no longer had the correct magnetisation) due to ad-hoc degaussing (although, in retrospect, there's a good chance that was done with a magnetiser, which would explain it).
From: Michael A. Terrell on 24 Jun 2010 23:40 D Yuniskis wrote: > > Hi, > > A 501(3)c that I am affiliated with received a donation > of several hundred ~80G SATA/PATA drives the other day. > They have allegedly (?) been bulk erased. I was asked, > today, if there is any way to make the drives serviceable, > again. > > I have not seen the drives or had a chance to play with > any of them. As "proof" that they were bulk erased, I > am told each drive bears a label: > ERASED > Magnetic data is completely erased. > Erased product can't be reused or repaired. > > When *I* take a drive out of service, I "bulk erase" them > (after "electronically" overwriting the existing data) and > then subject them to the 500G drop test :> But, I'll admit > I have never *tried* to recover data from a drive thusly > (ahem) "treated". > > My initial response to them was "recycle them, they're trash". > Was I too hasty? > > I would imagine all the servo information, low level > formatting, bad sector table, etc. are gone or corrupted > so putting these back into service would require "special > factory tools"... There is a software command for newer drives to erase all data. -- Anyone wanting to run for any political office in the US should have to have a DD214, and a honorable discharge.
From: Grant on 25 Jun 2010 02:29
On Thu, 24 Jun 2010 23:40:18 -0400, "Michael A. Terrell" <mike.terrell(a)earthlink.net> wrote: > >D Yuniskis wrote: >> >> Hi, >> >> A 501(3)c that I am affiliated with received a donation >> of several hundred ~80G SATA/PATA drives the other day. >> They have allegedly (?) been bulk erased. I was asked, >> today, if there is any way to make the drives serviceable, >> again. >> >> I have not seen the drives or had a chance to play with >> any of them. As "proof" that they were bulk erased, I >> am told each drive bears a label: >> ERASED >> Magnetic data is completely erased. >> Erased product can't be reused or repaired. >> >> When *I* take a drive out of service, I "bulk erase" them >> (after "electronically" overwriting the existing data) and >> then subject them to the 500G drop test :> But, I'll admit >> I have never *tried* to recover data from a drive thusly >> (ahem) "treated". >> >> My initial response to them was "recycle them, they're trash". >> Was I too hasty? >> >> I would imagine all the servo information, low level >> formatting, bad sector table, etc. are gone or corrupted >> so putting these back into service would require "special >> factory tools"... > > > There is a software command for newer drives to erase all data. Yes, but it takes too long to execute for commercial reality? Bang a six inch nail through them, kills 'em dead in seconds ;) As far as attempted recovery goes, I'd connect one to a linux box and write zeroes to the entire drive. dd's terminating message will indicate whether the drive is worth formatting, as it will either report some error or it'll report writing 80GB of zeroes to the drive. Grant. -- http://bugs.id.au/ |