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dispose of storage devices while being certain the data is unrecoverable I use Derek's Boot and Nuke bootdisc for this purpose. http://www.dban.org/ http://ww

dispose of storage devices while being certain the data is unrecoverable I use Derek's Boot and Nuke bootdisc for this purpose. http://www.dban.org/ http://www.dban.org/ It's straightforward to use, but it's also configurable if you want to be extra certain the data is gone. I think the default is 3 passes of filling the harddrive with random data generated via Mersenne Twister.

omh 13y ago
Unless you're very paranoid then a single pass of zeroes should be sufficient. The bigger problem is what to to with a dead hard disk. It's usually easier to buy a new one rather than replace it, but an attacker could perhaps repair the disk to steal the data. At work we send any non-wipable disk to be physically shredded. At home I think I'd just hold on to all disks indefinitely.
- maxerickson 13y ago
  There's lots of ways to damage the platters, at which point the data probably won't justify exotic recovery methods. For a drive with bitcoin on it, just move the coins to new addresses before disposing of it.
- x3c 13y ago
  Open it, take the disc out and microwave it.
  - gmac 13y ago
    Dangerous?
    - ihsw 13y ago
      "Is It A Good Idea To Microwave An XBOX 360?" http://www.youtube.com/watch?v=vzodemYzswQ http://www.youtube.com/watch?v=vzodemYzswQ "Is It A Good Idea To Microwave A PlayStation 3?" http://www.youtube.com/watch?v=4rWyJXpezPs http://www.youtube.com/watch?v=4rWyJXpezPs "Is It A Good Idea To Microwave A Nintendo Wii?" http://www.youtube.com/watch?v=OydTZpbp0EE http://www.youtube.com/watch?v=OydTZpbp0EE
- atwebb 13y ago
  Drive a few nails through the case, it's fun and destructive! When drives were much larger, we used to take them apart, use the platter for mirrors/silly decorations and the magnets to magnetize tools around the office.
- bluedino 13y ago
  >> Unless you're very paranoid then a single pass of zeroes should be sufficient. If you're paranoid it won't matter how many passes of zeroes you do. After 1 it's done. If you're still paranoid, hard drives make great rifle targets.
willvarfar 13y ago
These days there is a proper secure wipe built into most drives themselves. Its part of the ATA spec. https://ata.wiki.kernel.org/index.php/ATA_Secure_Erase https://ata.wiki.kernel.org/index.php/ATA_Secure_Erase Yet if you ask how to wipe a disk on a forum, you'll get user-space ideas like `dd` and `shred` :(
- techdragon 13y ago
  A lot of people want a more physically certain level of data destruction than such a command provides. If I saw that a drive wrote 3-5 passed of junk data before zeroing the disk then I would trust it but such firmware level info is rare to impossible up find.
  - phamilton 13y ago
    Many SSDs do on the fly AES encryption. Secure wipe is then just a destruction of the private key. All the encrypted data stays put.
    - venomsnake 13y ago
      Since when there is private key in AES? And that requires a paranoid person to trust that a company does not holds the keys in escrows somewhere or are by any way retrievable.
KiwiCoder 13y ago
To clarify - the hard part is not the destruction of data you know about, it's the identification of data on devices you don't know about, or forget. Computers with hard disks are obvious, but also consider mobile phones, tablets, games devices (that increasingly ask for sensitive information), PVRs, and so on. There may be a point, if we haven't already reached it, where I can't dispose of a toaster without worrying about how to wipe its memory.
- jzwinck 13y ago
  Don't forget office printers! Some have hard drives or other nonvolatile storage. You know, in case you want to run off a second copy of that fax from 2009.
dzhiurgis 13y ago
How about cat /dev/random > file ?
- Anderkent 13y ago
  Doesn't that effectively do: unlink(filename) create(filename) write(filename, random) ? Though something that opens the file in append mode then seeks to 0 would probably overwrite the same HDD locations.
  - finnw 13y ago
    Yes. It will truncate the file first, then allocate new blocks for the new random data, likely leaving the old blocks lying around. You can avoid this with the 'conv=notrunc' option of 'dd'[1]. It will overwrite existing blocks instead of truncating (and possibly reallocating): notrunc Do not truncate the output file. This will preserve any blocks in the output file not explicitly written by dd. The notrunc value is not supported for tapes. [1]:https://developer.apple.com/library/mac/documentation/Darwin/Reference/ManPages/man1/dd.1.html https://developer.apple.com/library/mac/documentation/Darwin...
    - dzhiurgis 13y ago
      Do you mean that the system will try to compress whatever gigabytes of random data?
      - finnw 13y ago
        No, I mean it will store the new random data in different blocks, thus not overwriting the old blocks.
        dzhiurgis 13y ago
        Even if the whole drive is 'empty' ?
pbhjpbhj 13y ago
DBAN's good, there are a couple of other ways I've used including dd. Here's a blog post about it http://alicious.com/secure-drive-data-wiping/ http://alicious.com/secure-drive-data-wiping/ including references to some papers where they looked at the probability/possibility of recovery.

omh 13y ago

Unless you're very paranoid then a single pass of zeroes should be sufficient. The bigger problem is what to to with a dead hard disk. It's usually easier to buy a new one rather than replace it, but an attacker could perhaps repair the disk to steal the data. At work we send any non-wipable disk to be physically shredded. At home I think I'd just hold on to all disks indefinitely.

maxerickson 13y ago
There's lots of ways to damage the platters, at which point the data probably won't justify exotic recovery methods. For a drive with bitcoin on it, just move the coins to new addresses before disposing of it.
x3c 13y ago
Open it, take the disc out and microwave it.
- gmac 13y ago
  Dangerous?
  - ihsw 13y ago
    "Is It A Good Idea To Microwave An XBOX 360?" http://www.youtube.com/watch?v=vzodemYzswQ http://www.youtube.com/watch?v=vzodemYzswQ "Is It A Good Idea To Microwave A PlayStation 3?" http://www.youtube.com/watch?v=4rWyJXpezPs http://www.youtube.com/watch?v=4rWyJXpezPs "Is It A Good Idea To Microwave A Nintendo Wii?" http://www.youtube.com/watch?v=OydTZpbp0EE http://www.youtube.com/watch?v=OydTZpbp0EE
atwebb 13y ago
Drive a few nails through the case, it's fun and destructive! When drives were much larger, we used to take them apart, use the platter for mirrors/silly decorations and the magnets to magnetize tools around the office.
bluedino 13y ago
>> Unless you're very paranoid then a single pass of zeroes should be sufficient. If you're paranoid it won't matter how many passes of zeroes you do. After 1 it's done. If you're still paranoid, hard drives make great rifle targets.

willvarfar 13y ago

These days there is a proper secure wipe built into most drives themselves. Its part of the ATA spec. https://ata.wiki.kernel.org/index.php/ATA_Secure_Erase https://ata.wiki.kernel.org/index.php/ATA_Secure_Erase Yet if you ask how to wipe a disk on a forum, you'll get user-space ideas like `dd` and `shred` :(

techdragon 13y ago
A lot of people want a more physically certain level of data destruction than such a command provides. If I saw that a drive wrote 3-5 passed of junk data before zeroing the disk then I would trust it but such firmware level info is rare to impossible up find.
- phamilton 13y ago
  Many SSDs do on the fly AES encryption. Secure wipe is then just a destruction of the private key. All the encrypted data stays put.
  - venomsnake 13y ago
    Since when there is private key in AES? And that requires a paranoid person to trust that a company does not holds the keys in escrows somewhere or are by any way retrievable.

KiwiCoder 13y ago

To clarify - the hard part is not the destruction of data you know about, it's the identification of data on devices you don't know about, or forget. Computers with hard disks are obvious, but also consider mobile phones, tablets, games devices (that increasingly ask for sensitive information), PVRs, and so on. There may be a point, if we haven't already reached it, where I can't dispose of a toaster without worrying about how to wipe its memory.

jzwinck 13y ago
Don't forget office printers! Some have hard drives or other nonvolatile storage. You know, in case you want to run off a second copy of that fax from 2009.

dzhiurgis 13y ago

How about cat /dev/random > file ?

Anderkent 13y ago
Doesn't that effectively do: unlink(filename) create(filename) write(filename, random) ? Though something that opens the file in append mode then seeks to 0 would probably overwrite the same HDD locations.
- finnw 13y ago
  Yes. It will truncate the file first, then allocate new blocks for the new random data, likely leaving the old blocks lying around. You can avoid this with the 'conv=notrunc' option of 'dd'[1]. It will overwrite existing blocks instead of truncating (and possibly reallocating): notrunc Do not truncate the output file. This will preserve any blocks in the output file not explicitly written by dd. The notrunc value is not supported for tapes. [1]:https://developer.apple.com/library/mac/documentation/Darwin/Reference/ManPages/man1/dd.1.html https://developer.apple.com/library/mac/documentation/Darwin...
  - dzhiurgis 13y ago
    Do you mean that the system will try to compress whatever gigabytes of random data?
    - finnw 13y ago
      No, I mean it will store the new random data in different blocks, thus not overwriting the old blocks.
      - dzhiurgis 13y ago
        Even if the whole drive is 'empty' ?

pbhjpbhj 13y ago

DBAN's good, there are a couple of other ways I've used including dd. Here's a blog post about it http://alicious.com/secure-drive-data-wiping/ http://alicious.com/secure-drive-data-wiping/ including references to some papers where they looked at the probability/possibility of recovery.