Fast and secure HDD erase?

Hi,

i wonder, is there a faster alternative than to overwrite a HDD n-times,
if i want the data reasonably securely destroyed (without destroying the HDD
itself)?
I got the problem that i have 4 x 250GB HDDs which need to be erased.
But with the deletion tools i know, which overwrite the whole disk n-times
it takes me up to 2 days just for one of them.


thanks,
rob

Robert Wegner

"Robert Wegner" <> wrote in message
news: ...
> Hi,
>
> i wonder, is there a faster alternative than to overwrite a HDD n-times,
> if i want the data reasonably securely destroyed (without destroying the
> HDD
> itself)?
> I got the problem that i have 4 x 250GB HDDs which need to be erased.
> But with the deletion tools i know, which overwrite the whole disk
> n-times
> it takes me up to 2 days just for one of them.
>
>
> thanks,
> rob
>
The new DoD standard states that hdd's above 15GB can be erased with one
over write.

I generally use Maxtor low level format and write 3 times.

hdtv?

Robert Wegner wrote:

> Hi,
>
> i wonder, is there a faster alternative than to overwrite a HDD n-times,
> if i want the data reasonably securely destroyed (without destroying the HDD
> itself)?

Yes. A very large magnet. In fact the US military is implementing a
magnetic erase feature for the hard drives in aircraft flight recorders
and such so that downed planes can't reveal useful information. It's
thought to be more thorough and secure than conventional methods.

You'd have to research the ramifications, but if you believe it
wouldn't destroy consumer quality drives you might look for a local
tool or machine shop that has what's called a "demagnetizer". You might
want to remove the drive controller first, I'm not sure how something
like that would affect the electronics. Not as big a project as you'd
think with most drives, just a couple screws and a connector.

If you want to spend the money, several companies make drive degauss
tools. Fujtsu calls theirs "Mag EraSURE", but I'm not sure what it
costs or how secure it is. I'd imagine it's secure enough just to pass
the drive on to an average Joe. Google is your friend, I'd start with
something like 'bulk hard drive erasure'.

George Orwell

"Robert Wegner" <> wrote in message
news: ...
> Hi,
>
> i wonder, is there a faster alternative than to overwrite a HDD n-times,
> if i want the data reasonably securely destroyed (without destroying the
> HDD
> itself)?
> I got the problem that i have 4 x 250GB HDDs which need to be erased.
> But with the deletion tools i know, which overwrite the whole disk
> n-times
> it takes me up to 2 days just for one of them.
>
>
> thanks,
> rob

First, go back to the thread here of Aug31 'can't find an answer'.
Then consider the value and sensitvity of the data.
Is somebody going to want to look at many millions of sectors and try to
reconstruct files?
Or take the drive apart and examine the platters?
If not, then a few formats, preferable with different file systems will do
ie do it in ntfs, then fdisk, delete partitions, do it in fat32, delete,
then in a linux file system.
That will slow them down enough that it is no longer worth the effort unless
this might be evidence in a criminal trial.

Stuart

Stuart Miller

In Message-ID:<> ,
Robert Wegner <> wrote:

>i wonder, is there a faster alternative than to overwrite a HDD n-times,
>if i want the data reasonably securely destroyed (without destroying the HDD
>itself)?
>I got the problem that i have 4 x 250GB HDDs which need to be erased.
>But with the deletion tools i know, which overwrite the whole disk n-times
>it takes me up to 2 days just for one of them.

I'm not one of the deep experts that hangs out here, but I
strongly expect that the answer is "No".

However, in order to speed up your erasure, have you
considered:

1. Running all 4 at the same time? Depending on where the
slow-down is, this could take anywhere from 25% of the time up to
a bit over 100%.

2. What do you have "n" set to? Would you feel comfortable
lowering it to, say, 2? I think that even n=1 would stymie
anything short of clean-room techniques. (Would a real expert
comment on my n=1 conjecture, please?)

3. Start the erasures, now. By the time you get enough people to
answer this, you could probably have at least one of them already
erased.

--
Arthur T. - ar23hur "at" intergate "dot" com
Looking for a good MVS systems programmer position

Arthur T.

George Orwell wrote:

> Robert Wegner wrote:
>
>> Hi,
>>
>> i wonder, is there a faster alternative than to overwrite a HDD n-times,
>> if i want the data reasonably securely destroyed (without destroying the HDD
>> itself)?
>
> Yes. A very large magnet.

Keeping the HDD intact doesn't mean that you're supposed to magnetize the
package and destroying the electronics around the plates.

Sebastian Gottschalk

On Tue, 12 Sep 2006, in the Usenet newsgroup alt.computer.security, in article
<H6zNg.43989$ok5.278@dukeread01>, hdtv? wrote:

>"Robert Wegner" <> wrote

>> i wonder, is there a faster alternative than to overwrite a HDD n-times,
>> if i want the data reasonably securely destroyed (without destroying the
>> HDD itself)?

Who is your adversary? What is your threat model? What was on the disk?

>> I got the problem that i have 4 x 250GB HDDs which need to be erased.
>> But with the deletion tools i know, which overwrite the whole disk
>> n-times it takes me up to 2 days just for one of them.

2 days = 48 hours. 250 Gigs/48 hours = 5.2 Gigs/Hr = 1.45 Megabytes/second,
or about 4.5 Megabytes/second for a three wipe ("1's", "0's", random). That
seems extremely slow.

>The new DoD standard states that hdd's above 15GB can be erased with one
>over write.

Got a cite for that? A fast google search doesn't turn up anything recent,
and all I can find is NISPROM. Also, what level of classification does this
refer to? None, Confidential, Secret? Certainly anything above Secret
requires the physical destruction of the media.

Old guy

Moe Trin

Sebastian Gottschalk wrote:

> George Orwell wrote:
>
> > Robert Wegner wrote:
> >
> >> Hi,
> >>
> >> i wonder, is there a faster alternative than to overwrite a HDD n-times,
> >> if i want the data reasonably securely destroyed (without destroying the HDD
> >> itself)?
> >
> > Yes. A very large magnet.
>
> Keeping the HDD intact doesn't mean that you're supposed to magnetize the
> package and destroying the electronics around the plates.

People degauss hard drives every day without destroying them, dumbass.
And the poster clearly stated there was issues that needed to be
addressed if doing it "down and dirty". So you're either too stupid to
understand what you read, or to lazy to read it.

You're also proven a liar once again because you replied to a post
originating from a place you claimed to have killfiled. A pathetic
liar no less, who announces plonks like a rube and then doesn't actually
do the deed.

Free clue Gobblesnot: You threatening to ignore someone is a joke, not
a threat.

Borked Pseudo Mailed

Borked Pseudo Mailed <> wrote in
news: d.net:

> People degauss hard drives every day without destroying them, dumbass.


You may wish to reconsider.

With any modern drive a thorough degaussing would erase the servo tracks as
well as user data and render the drive useless (the manufacturer, the only
fellow who could realistically reestablish the servo tracks, is almost
certainly not going to be willing to do this on a used drive. Even if he
were willing, the cost would make it a very unappealing approach.)

Moreover, the coercivity of the magnetic materials used in today's drives
is so high that enormous fields have to be applied (an 8000 Oersted
external field applied through the case is required to reliably erase
typical 4000 Oe disk material). A field of this magnitude will mangle the
heads and risks distorting the disks themselves.

In short, degaussing effective enough to erase data is certain to ruin the
drive.

Regards,

nemo_outis

"nemo_outis" <> wrote in
news:Xns983D96EB791CAabcxyzcom@127.0.0.1:

> Borked Pseudo Mailed <> wrote in
> news: d.net:
>
>> People degauss hard drives every day without destroying them,
>> dumbass.
>
>
> You may wish to reconsider.
>
> With any modern drive a thorough degaussing would erase the servo
> tracks as well as user data and render the drive useless (the
> manufacturer, the only fellow who could realistically reestablish the
> servo tracks, is almost certainly not going to be willing to do this
> on a used drive. Even if he were willing, the cost would make it a
> very unappealing approach.)
>
> Moreover, the coercivity of the magnetic materials used in today's
> drives is so high that enormous fields have to be applied (an 8000
> Oersted external field applied through the case is required to
> reliably erase typical 4000 Oe disk material). A field of this
> magnitude will mangle the heads and risks distorting the disks
> themselves.
>
> In short, degaussing effective enough to erase data is certain to ruin
> the drive.
>
> Regards,
>

Here, as an example, is a slightly-behind-the-curve refurbished model that
produces 4000 Oe or so and can erase hard disk media up to about 2000 Oe
through the case. Note that the price makes even this used model
uneconomic unless its cost can be amortized against many, many drives.

http://www.datadev.com/ge4000.html

nemo_outis