From owner-freebsd-questions Sun Oct 6 5:57:49 2002 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 CAA8737B401 for ; Sun, 6 Oct 2002 05:57:47 -0700 (PDT) Received: from smtprelay8.dc2.adelphia.net (smtprelay8.dc2.adelphia.net [64.8.50.40]) by mx1.FreeBSD.org (Postfix) with ESMTP id E647143E6E for ; Sun, 6 Oct 2002 05:57:46 -0700 (PDT) (envelope-from barbish@a1poweruser.com) Received: from barbish ([68.65.175.62]) by smtprelay8.dc2.adelphia.net (Netscape Messaging Server 4.15) with SMTP id H3K9C900.D6H; Sun, 6 Oct 2002 08:57:45 -0400 Reply-To: From: "JoeB" To: "Jacob S. Barrett" Cc: Subject: RE: Block Zeroing Tool Date: Sun, 6 Oct 2002 08:57:44 -0400 Message-ID: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2911.0) In-Reply-To: <20021004143328.GC21868@dan.emsphone.com> X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 Importance: Normal Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG -----Original Message----- From: owner-freebsd-questions@FreeBSD.ORG [mailto:owner-freebsd-questions@FreeBSD.ORG]On Behalf Of Dan Nelson Sent: Friday, October 04, 2002 10:33 AM To: Jacob S. Barrett Cc: freebsd-questions@FreeBSD.ORG Subject: Re: Block Zeroing Tool In the last episode (Oct 04), Jacob S. Barrett said: > Is there a tool for FreeBSD that zeros the unallocated blocks on a > filesystem? > > The company I work for has an image on demand system for our lab > machines. This system relies on ghost which only supports file by > file imaging on certain file systems. I want to take disk images of > certain FreeBSD installations. Ghost will only take sector by sector > images of FreeBSD partitions. Since it is doing this it stores all > the "junk" unused blocks as well. This makes for a very large image > even with high compression. If I can zero out the unused blocks > before taking the image with high compression the image size should > be much smaller. > > So, is there utility to zero out those blocks? Does this make sense? > Is there a better way to take images of FreeBSD machines? dd if=/dev/zero of=filler bs=1m ; rm filler I also have tried to use ghost to make image backups of FBSD, but the image is the same size as the FBSD slice. Have you tested the solution posted above to zero out the unused disk space in the FBSD slice so ghost will only image bkup real data? Did it work like you hoped? To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message