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View Full Version : Looking for something to securely erase multiple HDs


arrow_runner
01-16-2009, 08:29 PM
I have SEVERAL used laptop hard drives I'd like to sell, but I would like to give them a good decent wipe before I do. Does anyone have some software to recommend? I don't want to use DBAN, I'd prefer something I can run from Windows or a Pre-installed Linux environment.

Thanks.

Majestic
01-16-2009, 08:48 PM
Hi,

I recently came into a similar situation where a client had his personal company accounting info on the work computer. They gave him the computer to retrieve the information but he wanted to make sure they could not get to his info since in a way they were competiting companies and now on bitter terms.

To make a long story short he wanted to ensure nobody could retrieve his info no matter what. At first I used something by Acronis ultimate disk eraser or something like that. I then used GetDataBack to see if I could get to any of the info.. well I could. In the end I used ERASER http://www.heidi.ie/node/14 and after using it the drive was completely zeroed. I couldn't get to the info using Pc Inspector nor GetDataBack. So, I highly recommend it.

Majestic

seedubya
01-16-2009, 09:43 PM
Eraser does exactly the same thing from within Windows. Does the DoD, Gutmann etc. up to 35 passes, I think. Obviously only to a secondary drive.

arrow_runner
01-16-2009, 09:49 PM
Sounds like I'll have to give Eraser a shot, thanks!

purple_minion
02-05-2009, 07:38 AM
I thought I'd chime in. In either DBAN or ERASER anything more then a few passes of psuedorandom data is a waste. Unfortunately I can't remember the exact location of where I read this, but the Gutmann 35 passes is a legacy from the past when harddrives used one of a few different methods of writing data to the drive, we're talking many many years ago. Now it's all propriatary methods that are pretty complex. I believe it was Gutmann himself that commented recently that a few passes of random LOOKING data will make any data irrecoverable, and that the magnetic microscope technique everyone is worried about is 1, VERY expensive (NSA expensive) 2, almost worthless. That being said, if it's something very very valuable/incriminating you could pulverize it but really from what I remember even a very slight bend in a disk so it's not flat makes it worthless. How they can't just adjust their equipment if it's not actually spinning the disk to read it I dunno, just what I read months ago. I personally just use eraser set to 2-3 passes of actual real random data (there is a checkbox somewhere) and make sure that ADS is checked. However, there is the possiblity that the data is physically somewhere on the drive from file moves, edits, defragging etc. The data at the end of a block goes with whatever file it's attached to until it's deleted, so if you write a file that says "Hi Mom!" and you have a 4kb block size, that file now has the data of "Hi Mom!" plus whatever was in the block before, could be something juicy. It's easy to check too, make a file in notepad and save it. Right click the text file and do properties, the difference between the size and the size on disk is the goodies that get carried around with that file where ever it goes! Mine is 7 bytes, but 4kb on disk. Waste of space too. Now think of all the partial blocks on your drive. On my system partition that is 8gb full the difference is a full 15mb, thankfull I have nothing lurking in this hidden data to worry about... well maybe my extreme midget ky wrestling with baby alligator porn, but other then that nothing.

Sorry to drone on, if you want good advice head over to the truecrypt forums, very knowledgable people. If you are truely worried about it better safe then sorry, no offense to anyone here. Security, from what I've read, is a VERY difficult subject to do correctly.

Jory
02-05-2009, 07:42 AM
1 pass with 'dd'

gunslinger
02-05-2009, 02:54 PM
Dban has always worked well for me.

Blues
02-05-2009, 03:09 PM
I did a data wipe for my dad a few years back he is a doctor so medical records must be destroyed from the drive. I used DBAN with 5 passes I think and then dismantled the drive physically and beat it over a anvil or sorts with a hammer. I think short of the government or a corrupt employee at such high tech high cost recovery facilities you have no hope of getting that data.

Note: The hammer was for my own amusement

arrow_runner
02-05-2009, 04:07 PM
Nice. And thanks to all who replied. I'm just going to use eraser or one of the Acronis utilities I purchased recently.

All I was looking for was a quick way to hot-swap a drive and do 1 'secure-random-data-erase' pass so I could tell customers with a good conscious that I took care of it if I'm recycling their laptop.