From owner-freebsd-fs@FreeBSD.ORG Fri Nov 25 00:15:50 2011 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id B6FB2106566B for ; Fri, 25 Nov 2011 00:15:49 +0000 (UTC) (envelope-from fjwcash@gmail.com) Received: from mail-vw0-f54.google.com (mail-vw0-f54.google.com [209.85.212.54]) by mx1.freebsd.org (Postfix) with ESMTP id 70C3D8FC12 for ; Fri, 25 Nov 2011 00:15:49 +0000 (UTC) Received: by vbbfa15 with SMTP id fa15so4004773vbb.13 for ; Thu, 24 Nov 2011 16:15:48 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=a2qrYiWIguVKkWpOsoLpABBoyEHGFW8uGX56TLUd+Ic=; b=fsuV+JNh8aKGp63Lipr1moE1IMpckuORo7RD68EVnmbjpzNKVF4XPIRdrAJWZUqvkl o/84XhHYVwPYbt85mL1pRMyURZH4jSIIAAt2of3cBFiMyRA944wVVQnRlZ5om3D42T0K 8yflDGNMeHxo9DPldx1VPQE0P86kVZNAHlpzE= MIME-Version: 1.0 Received: by 10.52.99.74 with SMTP id eo10mr14002270vdb.12.1322180148753; Thu, 24 Nov 2011 16:15:48 -0800 (PST) Received: by 10.220.190.71 with HTTP; Thu, 24 Nov 2011 16:15:48 -0800 (PST) In-Reply-To: References: <20111124235843.GB96603@johnny.reilly.home> Date: Thu, 24 Nov 2011 16:15:48 -0800 Message-ID: From: Freddie Cash To: Johannes Totz Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-fs@freebsd.org Subject: Re: backing up zfs dataset X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 25 Nov 2011 00:15:50 -0000 On Thu, Nov 24, 2011 at 4:12 PM, Johannes Totz wrote: > On 25/11/2011 00:07, Freddie Cash wrote: > >> On Thu, Nov 24, 2011 at 3:58 PM, Andrew Reilly** >> wrote: >> >> I do think that backup is something of a weakness for ZFS at >>> the moment. Sure, live filesystems and snapshots are clearly >>> cool, and the modern way and all, but there is an awful lot of >>> flexibility and ease of undersanding in the model of a "backup >>> file on a tape." Doesn't have to be on a tape, but the moral >>> equivalent to dump/restore would (in my book) be a wonderful >>> addition to ZFS, if anyone felt inclined. Just padding the >>> send/receive serialisation format with enough checksum and >>> restart information to allow detection and graceful recovery >>> from read errors in the backup medium would do the job. >>> >> >> >> One could probably work around this by doing a zfs send to a file, then >> running it through parchive [1] to generate all the redundancy data. >> Granted, I've never used par, so it may or may not be feasible. >> >> [1] http://parchive.sourceforge.**net >> > > yeah, was thinking of doing that at some stage. but then send/receive > format is not guaranteed to be stable (has anybody done any tests on this? > try a v1 send with a v28 receive?). > I haven't tried it, but the consensus I've seen on the zfs-discuss mailing list is that so long as the receive side is of a higher (or equal) version to the send side, it's supposed to work. In theory. ;) -- Freddie Cash fjwcash@gmail.com