From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bill Davidsen Subject: Re: Backups using RAID1 Date: Thu, 20 Nov 2008 17:20:00 -0500 Message-ID: <4925E290.4060500@tmr.com> References: <62c47030811191213n49a50624k4a0e167f20193a4@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Drew Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids Drew wrote: >> If you don't care about location-based risks (eg fire), then I don't >> see why you would bother removing the drives. Leaving disks in the >> machine basically only protects you against 'oops' moments (rm -rf and >> such like)., but not much else. >> > > In this instance location based risks (fire, earthquake) are a > concern. My original idea when I started exploring backup ideas was > something I could leave unattended to start when I went to bed and if > for some reason I was forced to evacuate in the wee hours of the > morning all I had to do was yank the drives from the server and leave. > > As far as oops moments, only the applications have direct access to > files on disk. All user access to disks is via Samba and I've enabled > the recycle bin vfs module. > > >> The advantage in RAID1 is that it makes a copy constantly, so it takes >> no time to create the backup - using other methods (rsync, tape, >> rdiff-backup) with a huge amount of data, this time can be >> prohibitive. >> > > That was part of why I was looking at RAID for the backup. I've also > had a few suggestions about getting an external eSATA drive and > leaving it plugged in overnight. Just have a cron job do a nightly > rsync or such and *if* I have to evacuate, hopefully rsync will be > complete. > > If you are that paranoid about the backup, get two and use a different one each night. You can run a cron job to back stuff up (I've done it) every half hour or so, given three checks: (a) is the last one finished, (b) is the last modified time > 30 minutes (ie. is it done), and (c) has it been modified more recently than the last backup (touch a file at the end of backup). Having dealt with both fire and earthquake, I doubt your wife will worry about the recordings, just getting the people and pets out, and whatever paperwork you have in your fireproof safe (in case time is tight). >> Also, I'd say that plugging/unplugging disks would historically be a >> problem, but SATA shouldn't be, IMO. Also, there are solutions >> specifically designed for plugging/unplugging - which makes the point >> moot - so you might consider one of those. >> > > My SATA controller supports hot plugging so I'm not worried there. > > > -- Bill Davidsen "Woe unto the statesman who makes war without a reason that will still be valid when the war is over..." Otto von Bismark