From mboxrd@z Thu Jan 1 00:00:00 1970 From: Phillip Susi Subject: Re: Using the dm tools to create a writable "mirror" of a physical disk Date: Wed, 02 Feb 2011 19:17:41 -0500 Message-ID: <4D49F425.1000203@cfl.rr.com> References: Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: device-mapper development Cc: Anders Andersson List-Id: dm-devel.ids On 02/02/2011 05:31 PM, Anders Andersson wrote: > Good evening! I was recently given the task of trying to salvage files > from a 1.5TB harddrive that was accidentally formatted and/or > repartitioned. Normally I would do a 1:1 copy of the whole drive to a > file and operate on that, but I simply do not have that much room this > time. > > Ideally I would like to create a writable snapshot in the same way as > I do with my LVM volumes, storing the changes in a smaller file or in > another block device so that I can experiment freely without worrying > about destroying anything else on the drive. Is this possible > (probably) and easy (probably not?) with any device mapper tools? I'm > not really sure where I should begin looking, because dmsetup is > probably pretty low-level. Yep, you need to use dmsetup. Documentation/device-mapper/snapshot.txt in the kernel sources documents how.