Bulk erased drives

HDD Low Level Format Tool Claims to be able to format the drive. List mfg's that are supported. Never tried it, but the low level formatting is done at the factory and I doubt it will work.

Cheers

There IS a market on eBay for drives FOR PARTS. People commonly replace bad circuit boards and they need exact matches.

Sometimes platters are swapped into good matching drives in efforts to retrieve information. I have no idea just what the success rate for this is. Clean room bypassed in hopes of just one read, perhaps a sector dump to be re-assembled elsewhere.

On the other hand hand, if the bulk eraser used on the drives greats the strong magnetic flux of one that I saw/used decades ago, I would wonder if the circuitry wouldn't be destroyed by the induced voltage and current.

Does anybody know what being run through a super strong cabinet style degausser does to small circuit boards?

Select a few that have freely available low level tools available from the manufacturers or a third party website. You have nothing to lose by powering them up and putting them onto a *sacrificial* interface card.

There is a possibility that the "bulk erased" drives also had their electronics "erased" or wrecked by the application of mains to the interface as well in which case they are beyond economic repair.

Possibly but be careful not to try them out in anything but a sacrificial old box that you do not care about.

They are available Google "Low level format diagnostics" eg Hitachi/IBM

You might get lucky, but I would be a bit reticent about storing anything I was fond of on recovered drives unless they were in a RAID array with suitable redundancy to protect data.

Regards, Martin Brown

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.

First, I'd try just powering it up with no data connection. If that doesn't work, I wouldn't bother too much about the other aspects.

It's a shame; unless you have wipe a hundred drives a day, there's no reason why you can't just erase the drive. I'm sure a lot of it is due to people having heard about Gutmann's paper but, being unable to make an informed assessment, opt for paranoia.

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.

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?

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.

I agree. That would be the easiest thing to do and still erase the data beyond recovery.

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...

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.

drives

I use old HDDs as targets at the firing range.

Vladimir Vassilevsky DSP and Mixed Signal Design Consultant

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).

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.

All programs i have seen "erase" the data by writing random data; what you call low leveel formatting is not changed, and there is no software available to do a TRUE low-level format; the ads _say_ that "low leel" formatting is done, but that is not the case. True low-level formatting is done at the factory with rather special software that builds a defect table and (in effect) a "these sectors are good" address table that makes it _LOOK_ like all resulting sectors are contiguous. Such software also adds in servo tracks and other servo info that you CANNOT read. So, IF any "diskwipe" program was used, the HD looks like a new drive, except that bad sectors will still be "available" (uses Spinrite to fix those). If one of those BIG electromagnets (like those used to lift cars and large scrap iron piles) was used, then you are SOL. Try a drive out; nothing to lose.

Diskwipe software over-writes ALL data, so there would be NO partition table in any sense of the term.

How many drives do you wipe per day? It's not like you have to stand there and watch it while it's erasing itself.

Physical destruction has the advantage that it's easy to verify, even by someone who doesn't understand the technology. If you have a molten blob or a pile of dust, it's immediately clear that no-one is going to recover data from it. For overwriting, it has to be taken on trust that you're not missing anything.

FWIW, the ATA Secure Erase feature is considered by NIST as preferable to software-based purging utilities (e.g. those targetting DoD 5220), as it's guaranteed to overwrite remapped sectors, "hidden" areas, etc which may be invisible to software tools.

Useful links:

Robert Baer, what was the most recent version of Spinrite before Gibson sold it to Microsoft?

I used to use Spinrite a LOT (system integrator) back on the old MFM and RLL hard disks.

Spinrite ceased to work it's magic and could not even be safely run on IDE drives when they came onto the scene. Did Gibson make a version later on that DID work well on IDE (ATA) drives?

Have you ever tried it?