How to erase data completely on HD

[satimis]

Hi folks,

OS Linux/Windows

What will be an easy and reliable way to completely erase a hard drive excluding with a hammer.

I have several 40G IDE Hard drives, running Linux or Windows, for disposal. A friend of mine needs them. I want completely erase all data before delivering them to him. Googling "How to completely erase a hard drive" brought me many suggestion. Please advise. TIA

B.R.
satimis

[Lakshmipathi]

Darik's Boot And Nuke | Hard Drive Disk Wipe and Data Clearing

[satimis]

Darik's Boot And Nuke | Hard Drive Disk Wipe and Data Clearing

Hi,

Thanks for your advise.

I will down following iso:
Darik's Boot and Nuke
dban-2.2.6_i586.iso

I suppose the CD burnt will boot the PC and erase the data on the HD disregarding the OS installed?

Setup on PC:-
Only the HD to be erased will be connected on the PC. The default HD will be disconnected temporarily.

B.R.
satimis

[Rubberman]

Get a quick-load USB disc enclosure, install and connect the drive (don't mount it). Note what device id is given it (/dev/sdX where X is some letter). Then, use the 'dd' command to erase it. For example, if the drive is /dev/sdh, you would do this (as root):

dd if=/dev/zero of=/dev/sdh

This will write zeros to the entire disc. This is not a certifiable forensic wipe of the drive, but it will certainly be adequate for your purposes.

[Lakshmipathi]

I suppose the CD burnt will boot the PC and erase the data on the HD disregarding the OS installed?

I haven't used that tool. I guess I should erase everything including installed OSes.

Rubberman's suggestion is also a good one. - Though I would suggest use random.

dd if=/dev/random of=/dev/sdh

If you think you have lot of time , then use live CD and mount these partitions and then use
"shred" command,to make content disk completely wiped out.

Having said that , in most case using simple dd,should be enough . Unless you are trying to hide a content from CIA

[Rubberman]

Lakshmi's suggestion of using /dev/random is a good one. I simply use /dev/zero myself when wiping discs that I want to use to install a new OS or give to someone else. In any case, either will work just fine. As I said, this will wipe the disc from casual access of the old data, though REALLY sophisticated tools can dig it out. The NSA requires that wiped discs be over-written 7 times with random bit patterns and then null bytes to be certifiably "clean". That's ok for small devices like your 40GB ones, but takes a HUGE amount of time for bigger discs like todays' 1+ TB size devices. So, if a 40GB disc takes 5 minutes to wipe once, and 35 minutes to wipe 7 times, a 1.5 TB disc will take almost 3 1/2 hours to wipe once and almost 24 hours to wipe to NSA requirements...

FWIW, if I had to thoroughly wipe a big disc, like 1+ TB in size, I think I'd just get a REALLY big electro-magnet, place it over the drive, and spin up the disc for a few minutes. That would probably randomize the data pretty thoroughly!

[Lakshmipathi]

Did you use shred for meet NSA requirement ? or simple dd .
Following shred command will overwrite file1 content 7 times and at final pass it zeroes out ,to hide shredding.

shred -zvn 7 file1

[satimis]

Did you use shred for meet NSA requirement ? or simple dd .
Following shred command will overwrite file1 content 7 times and at final pass it zeroes out ,to hide shredding.

Hi Lakshmipathi,

I never used shred before

$ which shred

/usr/bin/shred

It is running on Ubuntu 1004. Can it be used to delete all data on a HD? Thanks

B.R.
satimis

[Lakshmipathi]

yes,shred will work,but it will take long time to complete.

[satimis]

yes,shred will work,but it will take long time to complete.

Thanks

B.R.
satimis