How to securely erase a hard drive with both hardware and software

How to securely erase a hard drive with both hardware and software

Summary: Here are two hardware and software solutions, along with advice on how to deal with dead drives and solid-state drives.

TOPICS: Storage, Hardware

Time to answer a question from the Hardware 2.0 mailbox:

I have dozens of old hard drives about the place from old systems. Some are faulty, while others are the product of upgrading to bigger storage. I've now been ordered to get rid of these drives.

Can you suggest a way to securely wipe a hard drive?

Yes, I can. In fact, I'll give you a way to do it with hardware or software.

The best hardware solution I've come across is WiebeTech's Drive eRazer Ultra. This is not a cheap solution—the kit will set you back $249—but it will allow you to erase both SATA and PATA hard drives quickly and securely without having to tie a PC up to the job.

(Credit: WiebeTech)

If a hardware solution is a bit too pricey for you—and unless your job involves erasing hard drives, then it probably is—then an excellent software solution is to download Darik's Boot and Nuke (DBAN) and use this to erase the hard drives. DBAN is free hard drive 'nuking' software that allows you to securely wipe the data off your drive using a variety of overwrite patterns.

This will take a long time—longer if you choose the more secure erasure techniques—but it does a thorough job.

(Credit: DBAN)

There are two other things worth bringing up.

First, if you come across any drives that appear to be dead, remember that they will still hold information. If it is sensitive information, then these drives will need to be destroyed. A quick way to do this is to open up the drive, remove the platters, and run them over a strong magnet.

Alternatively, you can use a more dramatic method to destroy the drive, such as a sledgehammer, grinder, or even thermite, for that matter.

If you have solid-state drives (SSDs) then remember that these can be almost impossible to erase securely. The best way to do this I find it to use a whole-disk encryption tool—such as TrueCrypt—to encrypt the entire drive. If you use a really long key, then without this any data on the drive will be unrecoverable.

Topics: Storage, Hardware

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  • Warranty

    I have a Seagate drive that I can't read, just makes chunking sounds. It has a lot of personal info like taxes and such. It's under warranty so I can get it replaced for free but I have to trust them to wipe my data if they fix it. Any suggestions? I'm thinking about just drilling holes in the platters with a drill press and writing off the $80.
    • I doubt you can "trust" them

      They will probably replace the defective part, delete partitions, run a quick test, perhaps reset the firmware stats and send it back out as a warranty replacement. It will take far too much time for them to do a secure wipe on refurbs, unless they have some quick mechanical way of doing it, which I doubt.

      If you are really worried about it, don't waste your time drilling. A few good hammer blows on the cover should take care of things.
  • Target practice too

    "Alternatively, you can use a more dramatic method to destroy the drive, such as a sledgehammer, grinder, or even thermite, for that matter."

    You can also use them for target practice. If you don't have a fairly high-power rifle, in the U.S. you can rent guns fairly cheap at public shooting ranges.
  • Is it really dead?

    "I have a Seagate drive that I can't read, just makes chunking sounds."

    I had a drive recently that did that and the computer wouldn't boot. I wound up buying a new HD and reinstalling from a backup.

    After doing that, I hooked up one of those external adapters to change an IDE / SATA 3.5" / SATA 2.5" drive to USB (not an enclosure, just a power supply and adapter cable) and tried the drive again. Although I couldn't boot from it, I was able to access all the data on the drive. I wound up reformatting it and doing a full NTFS format, not Quick. It's working fine now and has not had any problems. (I have OS on an SSD, most data that doesn't change much on an internal "storage" HD and have a 200GB partition on that other HD for data that changes frequently, so I can back it up quickly.)

    The adapter setup sells for about $15 at Microcenter, so it's worth having around for troubleshooting or the occasional situation where you need an extra drive temporarily and you have an old one sitting around.
  • what do you recommend for mobile devices?

    people commonly sell their old phones and tablets. and obviously these drives are solid state. what do you recommend for mobile devices?
  • Hammer was the secure tool.

    I always used hammer to smash HD plate after opening it and crushed all visible chips with hammer. SSD just open it and hammer all the chips.
  • Try A Hard-Drive Shredder

    Software alone can never do it reliably.
  • Feedback

    Would like to know additional details with regards to this hardware device:
    - What is the basic amount of time to wipe what size(s)/type(s) of drives?
    - What effort(s) does it take with various defects a drive has?
    - What assurance or level of confidence does it provide that all parts are overwritten?
    - What log(s) are provided of execution status?

    With regards to "Darik's Boot And Nuke"
    - What type of 'free' is it?
    - Is it bootable, or an installed application?
    - Does it handle Linux or Solaris drives as well as those for Windoze?
    - Can it be used from a thumbdrive or USB stick?
    - What hardware drives does it support (IDE, SCSI, RAID, SATA, PATA, SSD, etc.....)?
    - What assurance or level of confidence does it provide that all parts are overwritten?
    - Does it selectively destroy drives and/or partitions, or 'everything'?
    - What log(s) are provided of execution status?

    Please be more specific, and accurate, with regards to appropriate magnetic strength (gauss, oersteds, etc..), vice the simple-minded suggestion to "... run them over a strong magnet". Your off-hand suggestion would mislead someone to think they were successful.

    Proper application of the hammer on platters of spinning-type drives is good. Bang on the edges, as well as the flat of both sides in numerous places. The goal here is to seriously deform the surface. A grinder is good. There is zero value in destroying 'chips' for drives with spinning platters. No individual has thermite --- don't be silly in suggesting it. Though fire/flame from a blow-torch (much more common than thermite) to all surfaces of the platter would be very successful.

    Your suggestion for whole-disk encryption for SSD drives needs to further state doing so at the time of installation/creation, or at least long before the need for destruction is upon you.
  • Parted Magic Boot CD or USB

    Boot up Parted Magic via CD or USB and use Secure Erase on any modern hard drive. Parted Magic is a Linux live boot distribution. Secure Erase is part of the ATA specification and about all the hard drives in 10 years support it. It will erase parts of the drive that DBAN can't and it will do it MANY times quicker because the erase is part of the firmware. If the drive has built in encryption, its instant. Otherwise figure 20 minutes to 2 hours depending on how big the drive and it can erase as many drives in parallel as you have SATA ports, usually 4.

    However, there is a fallback to use DBAN for older PATA drives, SCSI, etc. Also you sometimes have to "trick" certain SATA drives to unlocking due to BIOS locks that are implemented to prevent secure erase happening by accident (virus, etc). Most of the time just sleep the PC with the Secure Erase tool and it will unlock, but sometimes you have to hot plug the drive. We've erased well over 1000 SATA drives with this tool.
  • Old hard drives .... most work on with a USB adapter

    I have multiple HDDs that died and not one single computer would recognize them. But when I hooked them to a cheap ($20) XION SATA/IDE to USB adapter, I was able to access the data and wipe them all (using Eraser) without a problem.

    So my 1st suggestion, before spending $250 on a gadget that you will barely use, just try hooking the drive to an external case (if you have one .... many sell for $10 or less) or get a cheap SATA/IDE to USB adapter. Chances are you will be able to RECOVER the lost data before the drive is officially trashed.
  • Built-in Tools

    Windows, starting with 2000, has a built-in cipher tool which can encrypt the data in free space of hard drives.
    So I just format the drive and garble the free space with: cipher /W
    It will use industrial strength AES-256 encryption to scramble those free spaces.

    Only available for Pro versions and not possible in Home versions of windows though.
    I am sure there are similar tools for Linux distros also, as mentioned by the author, and TrueCrypt is one of them.
  • The drive comes with it's own way of erasing itself.

    Inside the drive, there is a very strong rare earth magnet that is used to actuate the head arm.
    Remove the magnet assembly and pass it over the platters. Instant data trash.
    • Re: Inside the drive, there is a very strong rare earth magnet

      Static magnetic fields alone are not enough to erase magnetically-recorded data, you need rapidly-varying fields.

      This was demonstrated in the old days by using those big electromagnets they have to lift the cars in wrecking yards, to pick up a stack of magnetic tapes, and then showing that the tapes could still be read without errors afterwards.
  • Boot up a usb pen drive with your fav Linux Distro

    Let's say drive c: is /dev/sda

    from a terminal window:

    dd if=/dev/zero of=/dev/sda bs=64M conv=notrunc
    Dietrich T. Schmitz + Your Linux Advocate
  • Drop Saws are good

    Added bonus - you can rescue the magnets. Everyone should have a few magnets on their desk.
  • fire

    Campfire plus bucket plus platters equals molten aluminum. Good luck trying to recover from that state.
    Linux uSer
  • Nuk´em!

    Dea Adrian,
    Here in Rio de Janeiro we are constantly looking for any lame excuse to throw a BBQ with lots of beer & friends. BBQs & HDs mix rather well if in fact you let them slow roast remembering to turn them as they as they change to various shades of black. When they make that sure fire sound of air whooshing and pop...pop...pop you know they´re really done! Love to see CSI retrieve info after that!
    C´mon down homeboy.
  • ErAce

    Software can be downloaded from It will over write whole hard disk 1-100 times. So user can select erase process to fill any security standard