From owner-freebsd-questions Wed May 9 17:35:40 2001 Delivered-To: freebsd-questions@freebsd.org Received: from guru.mired.org (okc-65-26-235-186.mmcable.com [65.26.235.186]) by hub.freebsd.org (Postfix) with SMTP id 50F5637B422 for ; Wed, 9 May 2001 17:35:38 -0700 (PDT) (envelope-from mwm@mired.org) Received: (qmail 23383 invoked by uid 100); 10 May 2001 00:35:37 -0000 From: Mike Meyer MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Message-ID: <15097.57945.106659.703869@guru.mired.org> Date: Wed, 9 May 2001 19:35:37 -0500 To: "PC Doc" Cc: questions@freebsd.org Subject: Re: Use DD to make image copy of dual boot drive? In-Reply-To: <42114309@toto.iv> X-Mailer: VM 6.90 under 21.1 (patch 14) "Cuyahoga Valley" XEmacs Lucid X-face: "5Mnwy%?j>IIV\)A=):rjWL~NB2aH[}Yq8Z=u~vJ`"(,&SiLvbbz2W`;h9L,Yg`+vb1>RG% *h+%X^n0EZd>TM8_IB;a8F?(Fb"lw'IgCoyM.[Lg#r\ Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG PC Doc types: > Is copying the whole disk, sector by sector doable with DD? What would the > command be? I think the 'c' partition refers to the whole disk so I would > guess something like: > > dd if=/dev/rwd0c of=/dev/rw1c bs=??? I used to do backups - and run them - that way. On the other hand, that was a *long* time ago. > I'm not sure about the devices and what would be a good block size. Do I > need to use 512 bytes? The disks say: 32-bit mult-block-16 so that that mean > an "efficient" block size would be 16x512? Or would a track (63x512) be > better? As long as it's at least 512 bytes, things should work. On the other hand, the bigger you make it, the faster the copy will go, unless you force your system to start swapping. I used to do half-cylinder chunks, because a full cylinder would cause the 11/70 to start swapping. http://www.mired.org/home/mwm/ Independent WWW/Perforce/FreeBSD/Unix consultant, email for more information. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message