Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 3 Oct 2002 15:58:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 3 Oct 2002 15:58:22 -0400 Received: from hokua.cfht.hawaii.edu ([128.171.80.51]:21942 "EHLO hokua.cfht.hawaii.edu") by vger.kernel.org with ESMTP id ; Thu, 3 Oct 2002 15:58:20 -0400 Message-ID: <3D9CA1C7.2000405@cfht.hawaii.edu> Date: Thu, 03 Oct 2002 10:00:07 -1000 From: Kanoalani Withington User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:0.9.4) Gecko/20011019 Netscape6/6.2 X-Accept-Language: en-us MIME-Version: 1.0 To: Roy Sigurd Karlsbakk CC: jbradford@dial.pipex.com, jakob@unthought.net, linux-kernel@vger.kernel.org, linux-raid@vger.kernel.org Subject: Re: RAID backup References: <200210031120.g93BKLqK000216@darkstar.example.net> <200210031326.47386.roy@karlsbakk.net> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1805 Lines: 44 I have to pipe in here and agree that the idea of using a disk array alone for backups is not a sound idea. Sure, backing up 2Tb to an old exabyte drive isn't going to work, if you really have that much data you need some more modern equipment. Essentially I believe the idea of a redundant array sounds safer than it really is in practice, especially when dealing with very large arrays and with level 5 arrays. The reasons why this is so are manifold, suffice to say that a few years of actually using such devices shows that they have much more potential for catastrophic failure and latent failure (you don't know it's broken until you go to use it and find out it's broken) than a well designed tape archive or backup. Not that disk to disk backups are a completely bad idea. In my experience a combination works best. For example, automatic backups to reserved disks or disk arrays on remote systems every night, but once a week tape snapshots of that data. It's a lot of tapes but over time it will prove to be worthwhile. If the data volume is too high, simple backup scripts that write every file only once (essentially an archive) to tape to make it more practical. -Kanoa Roy Sigurd Karlsbakk wrote: >On Thursday 03 October 2002 13:20, jbradford@dial.pipex.com wrote: > >>Might it not be a good idea to DD the raw contents of each disk to a tape >>drive, just incase you fubar the array? It would be time consuming, but at >>least you could restore your data in the event that it gets corrupted. >> > >er > >16 120GB disks? > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/