On Tue, 2009-09-15 at 09:44 -0700, Lemseffer. Tahar (MSA) wrote: > Good morning All, > Is anyone familiar with C Unix
Yes. I'm sure you'll find a lot of company at LUGOD. However, this topic is better discussed on the mailing list vox. Vox-tech is used for specific technical questions. Also, this change of subject would warrant a new thread. > Thanks > T > > -----Original Message----- > From: vox-tech-boun...@lists.lugod.org > [mailto:vox-tech-boun...@lists.lugod.org] On Behalf Of Chanoch (Ken) > Bloom > Sent: Thursday, September 10, 2009 10:38 AM > To: lugod's technical discussion forum > Subject: Re: [vox-tech] Most efficient way to wipe hard drives > > On Thu, Sep 10, 2009 at 09:56:54AM -0700, Brian Lavender wrote: > > On Wed, Sep 09, 2009 at 09:20:30PM -0700, Bill Broadley wrote: > > > > > > Short answer, one wipe is enough (At least for NIST, and one of the > British > > > Infosec standards), wipes miss bad sectors, the ATA secure erase > command is > > > worth checking out. > > [snip] > > I think caching is a concern on some systems, so more wipes seems to > > magically make the write go to the actual media. But I would agree > with > > one wipe is probably enough. I had not thought about bad blocks. > > > > > > > > So if you don't use secure wipe and won't lose sleep at night over a > few bad > > > blocks being potentially recovered I'd recommend something like: > > > > > > dd if=/dev/urandom of=/dev/sd<whichever disk> > > > > Your computer must have a lot of entropy! Note that that device > gathers > > entropy from the system. When an event happens, it may be worth one or > > two bits. Last time I wrote a program that read from that device, it > > seemed that I got a number of bytes, and then I had to wait as various > > events occured to the system. That is why they often tell you to move > the > > mouse around when generating keys. It generates entropy for the > system. > > /dev/random, blocks waiting for entropy. > /dev/urandom doesn't wait for entropy. It uses entropy if it's > avalable, and switches to a PRNG if there isn't enough entropy. I > think it's similar to what you suggest doing with AES. > > --Ken > _______________________________________________ vox-tech mailing list vox-tech@lists.lugod.org http://lists.lugod.org/mailman/listinfo/vox-tech