From owner-freebsd-usb@FreeBSD.ORG Sun Nov 21 07:24:01 2010 Return-Path: Delivered-To: freebsd-usb@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 38C2D106566B; Sun, 21 Nov 2010 07:24:01 +0000 (UTC) (envelope-from guru@unixarea.de) Received: from ms16-1.1blu.de (ms16-1.1blu.de [89.202.0.34]) by mx1.freebsd.org (Postfix) with ESMTP id 814488FC0C; Sun, 21 Nov 2010 07:24:00 +0000 (UTC) Received: from [88.217.28.104] (helo=current.Sisis.de) by ms16-1.1blu.de with esmtpsa (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.69) (envelope-from ) id 1PK4HF-0001u2-F2; Sun, 21 Nov 2010 08:23:57 +0100 Received: from current.Sisis.de (current [127.0.0.1]) by current.Sisis.de (8.14.3/8.14.3) with ESMTP id oAL7Nuwh069466; Sun, 21 Nov 2010 08:23:56 +0100 (CET) (envelope-from guru@unixarea.de) Received: (from guru@localhost) by current.Sisis.de (8.14.3/8.14.3/Submit) id oAL7NtJA069465; Sun, 21 Nov 2010 08:23:55 +0100 (CET) (envelope-from guru@unixarea.de) X-Authentication-Warning: current.Sisis.de: guru set sender to guru@unixarea.de using -f Date: Sun, 21 Nov 2010 08:23:54 +0100 From: Matthias Apitz To: perryh@pluto.rain.com Message-ID: <20101121072354.GA69433@current.Sisis.de> References: <201011191916.53655.hselasky@c2i.net> <4CE6C73A.4070208@FreeBSD.org> <20101120151655.GA4010@current.Sisis.de> <4ce865a4.aMSvcjRoHgImeAYF%perryh@pluto.rain.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <4ce865a4.aMSvcjRoHgImeAYF%perryh@pluto.rain.com> X-Operating-System: FreeBSD 8.0-CURRENT (i386) User-Agent: Mutt/1.5.19 (2009-01-05) X-Con-Id: 51246 X-Originating-IP: 88.217.28.104 Cc: mav@freebsd.org, freebsd-usb@freebsd.org Subject: Re: copying /dev/da0 with dd(1) to file: output differs X-BeenThere: freebsd-usb@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: Matthias Apitz List-Id: FreeBSD support for USB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 21 Nov 2010 07:24:01 -0000 El día Saturday, November 20, 2010 a las 04:19:48PM -0800, perryh@pluto.rain.com escribió: > ... > > What does this mean? Does not look like errors, in case of random > > error it whould be more caotic, or? > > Good question. > > To help sort out whether it matters, what happens if you read the > stick using dump(8) instead of dd (or mount it read-only and read it > with tar)? Either of those methods will read only the parts that > are in use. Good idea! A dump is fine and gives more or less the same size as the dump which was restored to the USB key: # dump -0au -f reRead.dmp /dev/da0s1a DUMP: Date of this level 0 dump: Sun Nov 21 08:05:25 2010 DUMP: Date of last level 0 dump: the epoch DUMP: Dumping /dev/da0s1a to reRead.dmp DUMP: mapping (Pass I) [regular files] DUMP: mapping (Pass II) [directories] DUMP: estimated 3282758 tape blocks. DUMP: dumping (Pass III) [directories] DUMP: dumping (Pass IV) [regular files] DUMP: 56.62% done, finished in 0:03 at Sun Nov 21 08:14:18 2010 DUMP: DUMP: 3287561 tape blocks on 1 volume DUMP: finished in 586 seconds, throughput 5610 KBytes/sec DUMP: level 0 dump on Sun Nov 21 08:05:25 2010 DUMP: Closing reRead.dmp DUMP: DUMP IS DONE current# ls -l reRead.dmp ~guru/usb9root.dmp -r--r--r-- 1 guru wheel 3351920640 12 nov 13:40 /home/guru/usb9root.dmp -rw-r--r-- 1 root wheel 3366461440 21 nov 08:15 reRead.dmp One could as well MD5 compare all files with find(1), but this is perhaps a bit overkill... I will buy a 2nd key and restore the dd(1)'ed file to it with dd(1)... matthias -- Matthias Apitz t +49-89-61308 351 - f +49-89-61308 399 - m +49-170-4527211 e - w http://www.unixarea.de/