Bulk erased drives
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From: Robert Roland on 24 Jun 2010 04:04 On Wed, 23 Jun 2010 19:19:02 -0700, D Yuniskis <not.going.to.be(a)seen.com> wrote: >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"... I'd say you are right. The key here is the servo information. The head positioning is done by a voice coil. A voice coil has no positional feedback, so the drive needs to read special information from the platters to figure out where the heads are at the moment. Once this information is lost from the platters, there is no way to locate the heads accurately. In the olden days, when the heads were moved by a stepper motor, a low level format was a simple matter. -- RoRo
From: AZ Nomad on 24 Jun 2010 10:22 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. Have you actually tried powering on a few and trying restore the partition table?
From: AZ Nomad on 24 Jun 2010 11:00 On Thu, 24 Jun 2010 09:02:30 +0100, Nobody <nobody(a)nowhere.com> 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.
From: Nico Coesel on 24 Jun 2010 13:02 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. -- Failure does not prove something is impossible, failure simply indicates you are not using the right tools... nico(a)nctdevpuntnl (punt=.) --------------------------------------------------------------
From: whit3rd on 24 Jun 2010 13:25
On Jun 23, 7:19 pm, D Yuniskis <not.going.to...(a)seen.com> wrote: > 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. > ... each drive bears a label: > ERASED > Magnetic data is completely erased. > Erased product can't be reused or repaired. Unless you have the phone number of the weenie who did the erasure, that label is meaningless (just someone's idea of a way to reassure his boss on the data security issue). Power a few and test 'em. Don't expect the drives to have much resale value, though... |