From owner-freebsd-hackers@FreeBSD.ORG Wed Oct 8 19:35:14 2008 Return-Path: Delivered-To: hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id A5D0D106568A for ; Wed, 8 Oct 2008 19:35:14 +0000 (UTC) (envelope-from zbeeble@gmail.com) Received: from wr-out-0506.google.com (wr-out-0506.google.com [64.233.184.230]) by mx1.freebsd.org (Postfix) with ESMTP id 55BFC8FC0A for ; Wed, 8 Oct 2008 19:35:14 +0000 (UTC) (envelope-from zbeeble@gmail.com) Received: by wr-out-0506.google.com with SMTP id c8so784035wra.27 for ; Wed, 08 Oct 2008 12:35:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to :subject:cc:in-reply-to:mime-version:content-type:references; bh=KoccRp5fL6mHHfy4GvIz2H9QmuAzc1rFwcX9oNNBSN8=; b=pbwnnd5ubag3bl3RkttDkqkNAWwko/ofs4IS+xT2YfpzZ6tDjeuHgQn0eTAa2k46mN wNeIY4+GU0L1wOzSZGdhPxoDKXp/1v6vcAdTS0wyCziIM+lD099ZbC9EMQjkaPPrq/4X luIz5CfgWvk2N2xPx2Oe5V3uo3OO3jQE54wqo= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version :content-type:references; b=WjxxgHsUB+/bi5yktmk0AsgfJa+0byW7/vHXgWh4k8eEfv0keu4jukQcSFkuGTsAgD avOOGnemzm6Wo393LBhkme0YxUl79gOYvrPuv35PfZE2l9JFz/g4AZquxnnVS3wKuQqj GREtRw/i5rvWAYknQXiqGPmp4vcjw/kgYvTKY= Received: by 10.231.38.67 with SMTP id a3mr456227ibe.29.1223494512533; Wed, 08 Oct 2008 12:35:12 -0700 (PDT) Received: by 10.150.137.11 with HTTP; Wed, 8 Oct 2008 12:35:12 -0700 (PDT) Message-ID: <5f67a8c40810081235k227dc870tce5fcbcbca61d3c1@mail.gmail.com> Date: Wed, 8 Oct 2008 15:35:12 -0400 From: "Zaphod Beeblebrox" To: "Evren Yurtesen" In-Reply-To: <48ECF564.7000204@ispro.net> MIME-Version: 1.0 References: <48E9E1BB.6020908@ispro.net> <48EA56BB.6040702@vwsoft.com> <48EA8B3A.3090609@ispro.net> <861vysiv9i.fsf@ds4.des.no> <5f67a8c40810070937r5ba89773ncee407ace25fa0dd@mail.gmail.com> <86iqs3sdtp.fsf@ds4.des.no> <5f67a8c40810081015p2c14e38evbeed0a97242a7c4a@mail.gmail.com> <48ECF564.7000204@ispro.net> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: Volker , =?ISO-8859-1?Q?Dag-Erling_Sm=F8rgrav?= , hackers@freebsd.org Subject: Re: continuous backup solution for FreeBSD X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 08 Oct 2008 19:35:14 -0000 On Wed, Oct 8, 2008 at 2:01 PM, Evren Yurtesen wrote: > Zaphod Beeblebrox wrote: > >> >> Wow... thanks for the flame, but there's no reason that the device that >> is receiving the hammer replication couldn't be on the other side of the >> globe and there's no reason it couldn't be considered a backup. Part of the >> advantage of the structure that allows you to efficiently select for new >> changes allows you to do the same kind of *backup* as they claim. >> >> > Wouldnt that device need to keep the whole filesystem? Like if you have 10 > machines with 10x 1GB drives (lets say each used about 250gb), you will need > 10TB disk space in the backup server? > Urm... I think everything we've been discussing here backs up the whole filesystem (it would be near impossible for a block-oriented system to do elsewise). I suppose you could do something with the archive bit or dump bits with a filesystem based backup. But anyways... in a filesystem based replication system, you'd need enough space to store the data and the history of the data. The sum of the history of the data could even exceed the size of the sum of the input disks. It could also be much smaller. It really depends on how much you change.