From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1KOwLv-0004SX-Dr for qemu-devel@nongnu.org; Fri, 01 Aug 2008 11:15:35 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1KOwLt-0004Rd-Kt for qemu-devel@nongnu.org; Fri, 01 Aug 2008 11:15:34 -0400 Received: from [199.232.76.173] (port=53315 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1KOwLt-0004RS-9u for qemu-devel@nongnu.org; Fri, 01 Aug 2008 11:15:33 -0400 Received: from mail-gx0-f23.google.com ([209.85.217.23]:62768) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1KOwLs-0008Rf-NV for qemu-devel@nongnu.org; Fri, 01 Aug 2008 11:15:32 -0400 Received: by gxk4 with SMTP id 4so1321173gxk.10 for ; Fri, 01 Aug 2008 08:15:31 -0700 (PDT) Message-ID: <48932870.4000507@codemonkey.ws> Date: Fri, 01 Aug 2008 10:14:56 -0500 From: Anthony Liguori MIME-Version: 1.0 Subject: Re: [Qemu-devel] PATCH: Control over drive open modes for backing file References: <20080731113120.GJ23888@redhat.com> <489203C9.1040607@codemonkey.ws> <20080731185956.GA26755@shareable.org> <48921481.7010606@codemonkey.ws> <20080801074607.GA12019@shareable.org> In-Reply-To: <20080801074607.GA12019@shareable.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Jamie Lokier wrote: > Anthony Liguori wrote: > >>> Can I arbitrarily branch off different snapshots within a single qcow2 >>> file? Can I delete the 'base' snapshots safely? Most important: what >>> happens if I have snapshots in a qcow2 file which has a base file, and >>> I type 'commit'? Does it corrupt all the snapshots, effectively? >>> >> snapshots are linear, not branching. And they are only every >> saved/loaded from the highest level qcow2 file. >> > > So if I understand that right, the 'commit' command (to write to the > base image) _will_ corrupt all the snapshots since they depend on the > base image and it just changed?? > Yes, so don't do that. BTW, commit is a pretty useless command IMHO. If you use it to save a snapshot of a disk image while the OS has it mounted, you're not getting a very good backup. Regards, Anthony Liguori Regards, Anthony Liguori > -- Jamie > > >