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May 19, 2015 - A Look At The New Commandlinefu
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Psst. Open beta.

Wow, didn't really expect you to read this far down. The latest iteration of the site is in open beta. It's a gentle open beta-- not in prime-time just yet. It's being hosted over at UpGuard (link) and you are more than welcome to give it a shot. Couple things:

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Securely destroy data on given device hugely faster than /dev/urandom

Terminal - Securely destroy data on given device hugely faster than /dev/urandom
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
4
Securely destroy data on given device hugely faster than /dev/urandom

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.

Alternatives

There are 3 alternatives - vote for the best!

Terminal - Alternatives
# 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
Tags: dangerous
2

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

Know a better way?

If you can do better, submit your command here.

What others think

I found a kernel module /dev/srandom on github (josenk/srandom) that replaces /dev/urandom to be over 40x faster then /dev/urandom.

dd if=/dev/srandom of=/dev/<your disk> bs=4096k
Comment by user182882 71 weeks and 4 days ago

Your point of view

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