From owner-freebsd-questions@FreeBSD.ORG Mon Jun 23 20:23:03 2008 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 4DC121065675 for ; Mon, 23 Jun 2008 20:23:03 +0000 (UTC) (envelope-from rsmith@xs4all.nl) Received: from smtp-vbr15.xs4all.nl (smtp-vbr15.xs4all.nl [194.109.24.35]) by mx1.freebsd.org (Postfix) with ESMTP id BA4208FC16 for ; Mon, 23 Jun 2008 20:23:02 +0000 (UTC) (envelope-from rsmith@xs4all.nl) Received: from slackbox.xs4all.nl (slackbox.xs4all.nl [213.84.242.160]) by smtp-vbr15.xs4all.nl (8.13.8/8.13.8) with ESMTP id m5NKN0dP000572; Mon, 23 Jun 2008 22:23:00 +0200 (CEST) (envelope-from rsmith@xs4all.nl) Received: by slackbox.xs4all.nl (Postfix, from userid 1001) id 2B46DBA9C; Mon, 23 Jun 2008 22:23:00 +0200 (CEST) Date: Mon, 23 Jun 2008 22:23:00 +0200 From: Roland Smith To: Andrew Falanga Message-ID: <20080623202259.GB97202@slackbox.xs4all.nl> References: <340a29540806231257x670cf398qc5bf11c396fd0afb@mail.gmail.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="xgyAXRrhYN0wYx8y" Content-Disposition: inline In-Reply-To: <340a29540806231257x670cf398qc5bf11c396fd0afb@mail.gmail.com> X-GPG-Fingerprint: 1A2B 477F 9970 BA3C 2914 B7CE 1277 EFB0 C321 A725 X-GPG-Key: http://www.xs4all.nl/~rsmith/pubkey.txt X-GPG-Notice: If this message is not signed, don't assume I sent it! User-Agent: Mutt/1.5.18 (2008-05-17) X-Virus-Scanned: by XS4ALL Virus Scanner Cc: FreeBSD Questions Subject: Re: Wipe a drive clean X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 23 Jun 2008 20:23:03 -0000 --xgyAXRrhYN0wYx8y Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jun 23, 2008 at 01:57:47PM -0600, Andrew Falanga wrote: > Hi, >=20 > I'm having no luck finding hits for "wipe drive" or "zero drive" in > the mail list archives and I can't believe I'm the first to ask this > question but here it is anyway. How can I simply write 0's across a > USB thumb drive?=20 I'm not sure about flash memory, but for a harddrive, simple writing 0's is not a secure way to delete data. It can still be recovered. > I'd rather not install a port, if I can avoid it. I Have a look at security/wipe. > was thinking that something like dd would work, but everything I've > tried thus far is not working. What suggestions does everyone have? I think the trick is to use the right block size. Try bs=3D512 or 2048 in your dd command. Use if=3D/dev/random instead of if=3D/dev/zero and repeat a couple of times. Note that wiping flash drives way will shorten the lifespan of the device. Roland --=20 R.F.Smith http://www.xs4all.nl/~rsmith/ [plain text _non-HTML_ PGP/GnuPG encrypted/signed email much appreciated] pgp: 1A2B 477F 9970 BA3C 2914 B7CE 1277 EFB0 C321 A725 (KeyID: C321A725) --xgyAXRrhYN0wYx8y Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (FreeBSD) iEYEARECAAYFAkhgBiMACgkQEnfvsMMhpyXbaACgjqcds4UFLJGVzzx0AzgjjPAq L6gAn2DJUmJNI4C1t3KNZlOxYvBViXOr =Ec8G -----END PGP SIGNATURE----- --xgyAXRrhYN0wYx8y--