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May 19, 2015 - A Look At The New Commandlinefu
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Securely destroy data on given device

Terminal - Securely destroy data on given device
# for i in $(seq 1 25); do dd if=/dev/urandom of=<your disk> bs=1M ; done
2009-09-29 07:12:34
User: danam
Functions: dd seq
Securely destroy data on given device

Intentional hash in the beginning. May run a looong time. Wipes your data for real. Was meant to be /dev/urandom - I mistyped it. :-)


There is 1 alternative - vote for the best!

Terminal - Alternatives
openssl enc -aes-256-ctr -pass pass:"$(dd if=/dev/urandom bs=128 count=1 2>/dev/null | base64)" -nosalt < /dev/zero > randomfile.bin
2014-06-02 18:12:54
User: malathion

This command generates a pseudo-random data stream using aes-256-ctr with a seed set by /dev/urandom. Redirect to a block device for secure data scrambling.

Know a better way?

If you can do better, submit your command here.

What others think

Wiping data multiple times is not necessary to be secure (http://www.h-online.com/news/Secure-deletion-a-single-overwrite-will-do-it--/112432).

So one time overwriting need less time and is secure enough.

Maybe random data could improve the security a bit further.

dd if=/dev/urandom of=<your disk> bs=1M

Or, if you guarantee to generate enough entropy on your system during the whole wiping process, an even more secure way:

dd if=/dev/random of=<your disk> bs=1M
Comment by Marco 446 weeks and 2 days ago

dd if=/dev/zero of=/dev/disk bs=2M conv=fdatasync

is good enough on modern disks, and much faster. In fact some drives have an inbuilt 'secure erase' feature which does almost exactly the same thing (in addition the 'secure erase' also overwrites any unused reallocated bad blocks)

Comment by Escher 446 weeks and 2 days ago


Comment by linuxrawkstar 446 weeks and 2 days ago

Your point of view

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