From owner-freebsd-questions@FreeBSD.ORG  Tue Aug 23 02:29:19 2005
Return-Path: <owner-freebsd-questions@FreeBSD.ORG>
X-Original-To: freebsd-questions@freebsd.org
Delivered-To: freebsd-questions@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 4265716A41F
	for <freebsd-questions@freebsd.org>;
	Tue, 23 Aug 2005 02:29:19 +0000 (GMT)
	(envelope-from Mike.Jeays@rogers.com)
Received: from smtp100.rog.mail.re2.yahoo.com (smtp100.rog.mail.re2.yahoo.com
	[206.190.36.78]) by mx1.FreeBSD.org (Postfix) with SMTP id AA3CD43D46
	for <freebsd-questions@freebsd.org>;
	Tue, 23 Aug 2005 02:29:18 +0000 (GMT)
	(envelope-from Mike.Jeays@rogers.com)
Received: (qmail 57788 invoked from network); 23 Aug 2005 02:29:17 -0000
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=rogers.com;
	h=Received:Subject:From:To:Cc:In-Reply-To:References:Content-Type:Message-Id:Mime-Version:X-Mailer:Date:Content-Transfer-Encoding;
	b=dy9bjYsFaUH32w7+xP4tz4PqBwEH+t5STyY65g+fEbLVx9cS6s8WJRzcqWVwEcca+N+kBG7sakNyJaXCIMH71yYCyymnNYtHIZZyluawstD/rbiGJeOmu8HgsYELQPe9E2/+QZVeHPbOYAtwStiVKh4kvxYbwmFrzj/sqZfxxVc=
	; 
Received: from unknown (HELO ?192.168.2.150?) (mjeays2551@24.114.152.139 with
	plain)
	by smtp100.rog.mail.re2.yahoo.com with SMTP; 23 Aug 2005 02:29:17 -0000
From: Mike Jeays <Mike.Jeays@rogers.com>
To: Danny MacMillan <flowers@users.sourceforge.net>
In-Reply-To: <430A7496.6080206@users.sourceforge.net>
References: <007301c5a755$ea1ee840$6701a8c0@monster>
	<430A7496.6080206@users.sourceforge.net>
Content-Type: text/plain
Message-Id: <1124764156.95639.3.camel@chaucer>
Mime-Version: 1.0
X-Mailer: Ximian Evolution 1.4.6 
Date: Mon, 22 Aug 2005 22:29:16 -0400
Content-Transfer-Encoding: 7bit
Cc: Sebastian Pahlke <sp.ibm@gmx.de>, freebsd-questions@freebsd.org
Subject: Re: dd is so slow on my SCSI disc
X-BeenThere: freebsd-questions@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: User questions <freebsd-questions.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>, 
	<mailto:freebsd-questions-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-questions>
List-Post: <mailto:freebsd-questions@freebsd.org>
List-Help: <mailto:freebsd-questions-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>, 
	<mailto:freebsd-questions-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 23 Aug 2005 02:29:19 -0000

On Mon, 2005-08-22 at 20:57, Danny MacMillan wrote:
> Sebastian Pahlke wrote:
> > Hi all,
> > 
> > I'm trying to "clean" a disc before selling them:
> > 
> > dd if=/dev/zero of=/dev/da0
> 
> You may want to consider using /dev/random instead of, or in combination
> with, /dev/zero.  Zeroing out a disk isn't a significant barrier to
> forensic analysis.
> 
> _______________________________________________
> freebsd-questions@freebsd.org mailing list
> http://lists.freebsd.org/mailman/listinfo/freebsd-questions
> To unsubscribe, send any mail to "freebsd-questions-unsubscribe@freebsd.org"

Using /dev/random is much, much slower than /dev/zero.