From owner-freebsd-questions Fri Dec 6 8:40:48 2002 Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 47F7E37B401 for ; Fri, 6 Dec 2002 08:40:47 -0800 (PST) Received: from smtp.infracaninophile.co.uk (happy-idiot-talk.infracaninophile.co.uk [81.2.69.218]) by mx1.FreeBSD.org (Postfix) with ESMTP id 4A18843EC5 for ; Fri, 6 Dec 2002 08:40:46 -0800 (PST) (envelope-from m.seaman@infracaninophile.co.uk) Received: from happy-idiot-talk.infracaninophile.co.uk (localhost [IPv6:::1]) by smtp.infracaninophile.co.uk (8.12.6/8.12.6) with ESMTP id gB6GegOR002143 for ; Fri, 6 Dec 2002 16:40:42 GMT (envelope-from matthew@happy-idiot-talk.infracaninophile.co.uk) Received: (from matthew@localhost) by happy-idiot-talk.infracaninophile.co.uk (8.12.6/8.12.6/Submit) id gB6Gebib002142 for freebsd-questions@FreeBSD.ORG; Fri, 6 Dec 2002 16:40:37 GMT Date: Fri, 6 Dec 2002 16:40:37 +0000 From: Matthew Seaman To: freebsd-questions@FreeBSD.ORG Subject: Re: clarification of man dump Message-ID: <20021206164037.GB1630@happy-idiot-talk.infracaninophi> Mail-Followup-To: Matthew Seaman , freebsd-questions@FreeBSD.ORG References: <20021206154739.GB69019@grummit.biaix.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20021206154739.GB69019@grummit.biaix.org> User-Agent: Mutt/1.5.1i X-Spam-Status: No, hits=-3.0 required=5.0 tests=IN_REP_TO,QUOTED_EMAIL_TEXT,REFERENCES,SPAM_PHRASE_00_01, USER_AGENT,USER_AGENT_MUTT version=2.43 Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Fri, Dec 06, 2002 at 04:47:39PM +0100, Joan Picanyol i Puig wrote: > Hi, > > I have some trouble understanding the last part of 'man dump', from "An > efficient method of...". My understanding is that the example means: > > 1. Take a level 0 dump once a month > 2. Take a level 1 dump once a week > 3. Take a level 3 dump on mondays, a level 2 on tuesdays, a level 5 on > wednesdays and so on until a level 9 on sundays. > > Am I missing something? What's so "efficient" from doing it this way > (why)? It's a compromise between minimising the number of tapes required to restore the system to the state it was in on any particular date --- clearly just taking a level 0 dump every day means you only have to restore from one tape set --- and getting the most data possible onto a limited number of backup tapes --- best economy is achieved by doing a full level 0 backup once, and then each day just doing an incremental backup of what changed since the previous day: however leave too long between level 0 dumps and you're likely going to have a real chore wading through a mountain of tapes to get back to any particular state. Cheers, Matthew -- Dr Matthew J Seaman MA, D.Phil. 26 The Paddocks Savill Way Marlow Tel: +44 1628 476614 Bucks., SL7 1TH UK To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message