From owner-freebsd-doc@FreeBSD.ORG Sat Jan 7 05:17:48 2012 Return-Path: Delivered-To: doc@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E9F8E1065677 for ; Sat, 7 Jan 2012 05:17:48 +0000 (UTC) (envelope-from kaduk@mit.edu) Received: from dmz-mailsec-scanner-6.mit.edu (DMZ-MAILSEC-SCANNER-6.MIT.EDU [18.7.68.35]) by mx1.freebsd.org (Postfix) with ESMTP id 883848FC14 for ; Sat, 7 Jan 2012 05:17:48 +0000 (UTC) X-AuditID: 12074423-b7f9c6d0000008c3-f1-4f07d57bb331 Received: from mailhub-auth-3.mit.edu ( [18.9.21.43]) by dmz-mailsec-scanner-6.mit.edu (Symantec Messaging Gateway) with SMTP id 05.5E.02243.B75D70F4; Sat, 7 Jan 2012 00:17:47 -0500 (EST) Received: from outgoing.mit.edu (OUTGOING-AUTH.MIT.EDU [18.7.22.103]) by mailhub-auth-3.mit.edu (8.13.8/8.9.2) with ESMTP id q075HlCr026371; Sat, 7 Jan 2012 00:17:47 -0500 Received: from multics.mit.edu (MULTICS.MIT.EDU [18.187.1.73]) (authenticated bits=56) (User authenticated as kaduk@ATHENA.MIT.EDU) by outgoing.mit.edu (8.13.6/8.12.4) with ESMTP id q075Hjhh008697 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Sat, 7 Jan 2012 00:17:47 -0500 (EST) Received: (from kaduk@localhost) by multics.mit.edu (8.12.9.20060308) id q075Hj2e014422; Sat, 7 Jan 2012 00:17:45 -0500 (EST) Date: Sat, 7 Jan 2012 00:17:44 -0500 (EST) From: Benjamin Kaduk To: Adam Vande More In-Reply-To: Message-ID: References: User-Agent: Alpine 1.10 (GSO 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrDIsWRmVeSWpSXmKPExsUixCmqrVt9ld3f4Mg0BYu9C+YzW0z9uJPV gcljxqf5LB47Z91lD2CK4rJJSc3JLEst0rdL4MqY2zyNpeAha8WGxw/ZGxhPsHQxcnJICJhI TGq+zwRhi0lcuLeerYuRi0NIYB+jxLVNp5lBEkIC6xklWi/4QST2M0ms/LuGESJRL7F/81pW EJtFQEvi8r9rYA1sAioSM99sZAOxRQS0Jdp2fALbwCwgLHH60l2wXmGgmqPdp8FsToFAiX/7 v4LV8ArYSzQdf8gEMT9A4u60y2AzRQV0JFbvn8ICUSMocXLmExaImZYS5/5cZ5vAKDgLSWoW ktQCRqZVjLIpuVW6uYmZOcWpybrFyYl5ealFumZ6uZkleqkppZsYQYHK7qK8g/HPQaVDjAIc jEo8vC+12P2FWBPLiitzDzFKcjApifLeugwU4kvKT6nMSCzOiC8qzUktPsQowcGsJML73Bco x5uSWFmVWpQPk5LmYFES59XQeucnJJCeWJKanZpakFoEk5Xh4FCS4D15BahRsCg1PbUiLTOn BCHNxMEJMpwHaPh+kBre4oLE3OLMdIj8KUZFKXHecyAJAZBERmkeXC8skbxiFAd6RZj3KEgV DzAJwXW/AhrMBDQ4SoQFZHBJIkJKqoHx2tcfZ8Nupe3/ERoioi519uFuSdNW3oLFs0Nnfzb7 2BgTERrw+uXptSyaK5SO69v8SZGdbNdVu4xlRdua8sOMdwOmOYq835BdeIqxeInFC+carilR 9R+dK2a4faktlt38ofxnXrqexr8tPbZCrsaXD3oWNCrpzzD1vLz77XPd1FUhCb6vLvkrsRRn JBpqMRcVJwIAwELch/8CAAA= Cc: doc@freebsd.org Subject: Re: Suggestion for Handbook X-BeenThere: freebsd-doc@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Documentation project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 07 Jan 2012 05:17:49 -0000 On Thu, 5 Jan 2012, Adam Vande More wrote: > This page contain info on creating a disk image: > > http://www.freebsd.org/doc/en_US.ISO8859-1/books/handbook/disks-virtual.html > > Of course the dd method works, but it might be better to use truncate(1) > instead of dd because it creates sparse files and is nearly as universal as > dd. > > E.g. "truncate -s 5k file.img" I think dd would be preferred precisely because it does not use sparse files -- all blocks for the image will be allocated. If a sparse file was used, and the physical disk became close to full, then when the system goes to make a write to the image and the backing file cannot be grown, things are unlikely to fail gracefully. -Ben Kaduk