From owner-freebsd-hackers@FreeBSD.ORG Wed Oct 8 20:03:39 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 AB3101065686 for ; Wed, 8 Oct 2008 20:03:39 +0000 (UTC) (envelope-from des@des.no) Received: from tim.des.no (tim.des.no [194.63.250.121]) by mx1.freebsd.org (Postfix) with ESMTP id 631FF8FC1F for ; Wed, 8 Oct 2008 20:03:39 +0000 (UTC) (envelope-from des@des.no) Received: from ds4.des.no (des.no [84.49.246.2]) by smtp.des.no (Postfix) with ESMTP id 9121E2049; Wed, 8 Oct 2008 22:03:38 +0200 (CEST) Received: by ds4.des.no (Postfix, from userid 1001) id 6D7B9844ED; Wed, 8 Oct 2008 22:03:38 +0200 (CEST) From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= To: Evren Yurtesen 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> Date: Wed, 08 Oct 2008 22:03:38 +0200 In-Reply-To: <48ECF564.7000204@ispro.net> (Evren Yurtesen's message of "Wed, 08 Oct 2008 21:01:08 +0300") Message-ID: <86r66qq2g5.fsf@ds4.des.no> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.0.60 (berkeley-unix) MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Cc: Volker , Zaphod Beeblebrox , 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 20:03:39 -0000 Evren Yurtesen writes: > 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? Yes and no and yes... It stores *changes* to the file systems, so how much space it needs depends on how full your file systems are, how often and how much you write to them, etc. Also, at every recovery point, you can discard all but the last change since the previous recovery point for every changed block. FWIW, the exact same answer applies to pretty much any backup solution that supports incremental backups. DES --=20 Dag-Erling Sm=C3=B8rgrav - des@des.no