cruelpupet

Anyone know of a good dos based hard drive eraser?


Something that will overwrite everything a few times

__________________
Am I alone here? Is that it?
Am I the only one who sees.

Maybe we can learn to be just like him.
Wear a little uniform.
Yes, sir.
No, sir.
Thank you, sir.

gear02

i know that the hard drive manufacturers (Maxtor, WD) have dos programs that do diags on a hard drive and will also do a low level format (writes 0s everywhere).

Jeffbx

http://www.sysinternals.com has one called Sdelete that's free. It's more for wiping individual files so it may take forever and a day to do an entire drive, but it should work.

Writing zeros is a good measure, but is not 100% secure. If you've got REALLY sensitive data, you'll want to do a more thorough wipe.

gear02

Writing zeroes isn't 100% secure? How so? What's a more thorough wipe?

Burzhui

there are tools out there that can restore contents of a hard drive after several formats... so no you are not totally secure

__________________
____________________
IF A FAT GIRL FALLS IN THE WOODS
DO THE TREES LAUGH?

gear02

But normal formats don't write 0s to the disk. That's why a low level format is different than a normal format.

I understand that if you use windows to format you can probably retrieve the information. But if you write a 0 to the whole disk, unless there's some sort of memory all you would get is a bunch of 0s.

LPMiller

there is always a memory of what was recorded before. You cannot fully erase it, due to the nature of how the hard drive stores information.

__________________
lpmiller
Chief News Editor
Nobel Prize Nominee
Reverend in the Universal Life Church
Once Shot A Man For Snoring Too Loud
Way Too Lazy To Change His Signature

"The strength to change what I can, the inability to accept what I can't, and the incapacity to tell the difference." - Calvin and Hobbes

attgig

__________________

Burzhui

i forgot to write low level... you can still retrieve info

bachviet

That would work.

__________________
Dell Dimension 9200 | Intel Core 2 Quad Q6600 (2.4GHz) | 4x1GB DDR2 | 256MB nVidia GeForce 8800GT

Dell Studio 17 | Intel Core i7-720QM (1.6GHz) | 2x2GB DDR3 1066MHz | 1GHz ATI Mobility Radeon HD 4650

Intel P4-C 3.0GHz | ECS 865PE-A | 3x512MB PC3200 | 128MB PNY GeForce 6600GT

Jeffbx

When you write all zeros, there's still a slight 'ghost' image of the data that used to be there.

For example, if you used to have a '1' at a particulat bit, writing zero over that will not actually return the magnetic field to a true zero as a result, but more like 0.01. For the hard drive electronics, that's close enough to be considered zero, so it reads it as such.

However, there are very sophisticated machines that can be used to read these faint ghost images, and completely return the entire hard drive to the state it was in before the wipe. I have known people to do this in cases of employee theft, people wiping their HDs when they get fired, etc. It's expensive, but has a very high success rate.

There are more sophisticated pieces of equipment that can even strip off 'layers' of formatting... enabling them to see things that have even been overwritten by other files. Of course, now you're into the CIA realm of tools, so it's not too likely that your average IT shop will have access to such things.

A better method of protection is to use a program like I mentioned above, that writes & re-writes random data over & over again. The more passes you do, the more secure the deletion is. The drawback is that it takes a loooong time.

Markel

Some "wipe" programs have an option of a "government wipe" which does something like write all ones then all zeros 5 times.

__________________
stay low... keep moving...

revil

there is a program called eraser (i think that's the name). it's free and lets you make a boot disk that will let you wipe a disk or certian partitions securly with several different algorithms to choose from.

GilbertsGrape

the only true way to erase sensitive information is to DEgause the harddrive which will in efect ruin the drive this is what we do to our drives that contain sensitive information at work

gear02

hmm...this is great to know...thanks guys!

Burzhui

you're complitely paranoid now... and you know it

Tommy Boomfiger

ive used Autoclave in the past. ive never had a reason to do more than 3 passes but it can do up to 25 structured passes (sorry, i dont know what a structured pass is). it will also probably take you a week to do that.

bigmontana

DBAN - Darik's Boot and Nuke - is a self-contained boot floppy that securely wipes the hard disks of most computers. It also meets DOD standards as you can set it to wipe 7 times. download it here - http://dban.sourceforge.net/

__________________
Michael Villani

Burzhui

what is this floppy you speak of?

bigmontana

Just go to the link and read about it, it will tell you all you know. There are two versions, floppy or cd. http://dban.sourceforge.net/

Booyamos

I usually just use this program that i found a while ago.

BCWIPE
http://www.jetico.com/index.htm#/faq.htm

i created a boot disk and use that, real easy, default is 7 passes i think, which takes about 4-6 hours. I start it and then check back the next day.

__________________
Boo ya Grandma