From owner-freebsd-questions@FreeBSD.ORG Thu Jan 17 22:24:30 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 E72BD16A418 for ; Thu, 17 Jan 2008 22:24:30 +0000 (UTC) (envelope-from brent.jones@otago.ac.nz) Received: from mailhub2.otago.ac.nz (mailhub2.otago.ac.nz [139.80.64.247]) by mx1.freebsd.org (Postfix) with ESMTP id 8A93E13C442 for ; Thu, 17 Jan 2008 22:24:30 +0000 (UTC) (envelope-from brent.jones@otago.ac.nz) Received: from its-ex-p04.registry.otago.ac.nz (its-ex-p04.registry.otago.ac.nz [10.4.15.133]) by mailhub2.otago.ac.nz (8.13.8/8.13.8) with ESMTP id m0HMORhb023479; Fri, 18 Jan 2008 11:24:28 +1300 Received: from its-ex-p04.registry.otago.ac.nz ([10.4.15.138]) by its-ex-p04.registry.otago.ac.nz with Microsoft SMTPSVC(6.0.3790.3959); Fri, 18 Jan 2008 11:24:27 +1300 Received: from MAIL1.registry.otago.ac.nz ([10.4.15.129]) by its-ex-p04.registry.otago.ac.nz with Microsoft SMTPSVC(6.0.3790.3959); Fri, 18 Jan 2008 11:24:27 +1300 X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Date: Fri, 18 Jan 2008 11:24:27 +1300 Message-ID: <31AE442CCBC1094ABC40CE85B0149F0652370B@MAIL1.registry.otago.ac.nz> In-Reply-To: <478F0D5A.9090107@highperformance.net> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: Gutman Method on Empty Space Thread-Index: AchY4HhOk9W3+Fq7TQGe4HoEL0pRsQAdc52w References: <478F0D5A.9090107@highperformance.net> From: "Brent Jones" To: "Jason C. Wells" , "freebsd general questions" X-OriginalArrivalTime: 17 Jan 2008 22:24:27.0822 (UTC) FILETIME=[B8D78CE0:01C85957] X-PMX-Version: 5.4.0.320885, Antispam-Engine: 2.5.2.313940, Antispam-Data: 2008.1.17.141150 X-PerlMx-Spam: Gauge=IIIIIII, Probability=7%, Report='BODY_SIZE_800_899 0, __CT 0, __CTE 0, __CT_TEXT_PLAIN 0, __HAS_MSGID 0, __IMS_MSGID 0, __MIME_TEXT_ONLY 0, __MIME_VERSION 0, __SANE_MSGID 0' Cc: Subject: RE: Gutman Method on Empty Space 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: Thu, 17 Jan 2008 22:24:31 -0000 > -----Original Message----- > From: owner-freebsd-questions@freebsd.org=20 > [mailto:owner-freebsd-questions@freebsd.org] On Behalf Of=20 > Jason C. Wells > Sent: Thursday, 17 January 2008 9:10 p.m. > To: freebsd general questions > Subject: Gutman Method on Empty Space >=20 > Can anyone recommend a utility for the secure overwriting of=20 > unused disc=20 > space? split -b 200m /dev/random randomdata ; sync && rm randomdata* Run as many times as your paranoia factor requires on your file system. Gutman suggests in his own writings that overwriting with random data makes the most sense with modern disks. Run as root to extend the writes past the soft filesystem limit. Use whatever split parameters you fancy for the file sizes. The "srm" port has fancy features for file/directory deletions. Cheers, Brent