From owner-freebsd-questions@FreeBSD.ORG Tue Aug 7 01:50:42 2007 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 9C6DD16A417 for ; Tue, 7 Aug 2007 01:50:42 +0000 (UTC) (envelope-from sudakov@sibptus.tomsk.ru) Received: from relay2.tomsk.ru (relay2.tomsk.ru [212.73.124.8]) by mx1.freebsd.org (Postfix) with ESMTP id DAB8B13C45A for ; Tue, 7 Aug 2007 01:50:41 +0000 (UTC) (envelope-from sudakov@sibptus.tomsk.ru) X-Virus-Scanned: by Dr.Web (R) daemon for FreeBSD, v4.33 at relay2.tomsk.ru Received: from [172.16.138.125] (account sudakovva@sibptus.tomsk.ru HELO admin.sibptus.tomsk.ru) by relay2.tomsk.ru (CommuniGate Pro SMTP 4.3.8) with ESMTPSA id 8374344 for freebsd-questions@freebsd.org; Tue, 07 Aug 2007 08:50:39 +0700 Received: (from sudakov@localhost) by admin.sibptus.tomsk.ru (8.13.6/8.13.6/Submit) id l771odJr039378 for freebsd-questions@freebsd.org; Tue, 7 Aug 2007 08:50:39 +0700 (OMSST) (envelope-from sudakov@sibptus.tomsk.ru) X-Authentication-Warning: admin.sibptus.tomsk.ru: sudakov set sender to sudakov@sibptus.tomsk.ru using -f Date: Tue, 7 Aug 2007 08:50:38 +0700 From: Victor Sudakov To: freebsd-questions@freebsd.org Message-ID: <20070807015038.GA39353@admin.sibptus.tomsk.ru> Mail-Followup-To: Victor Sudakov , freebsd-questions@freebsd.org References: <20070724115401.GA1355@admin.sibptus.tomsk.ru> <20070806025614.GA21368@admin.sibptus.tomsk.ru> <20070806071857.GA23813@admin.sibptus.tomsk.ru> <20070806110518.GA8074@epia-2.farid-hajji.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070806110518.GA8074@epia-2.farid-hajji.net> User-Agent: Mutt/1.4.2.1i Organization: AO "Svyaztransneft", SibPTUS X-PGP-Key: http://vas.tomsk.ru/vas.asc Subject: Re: dump -L X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 07 Aug 2007 01:50:42 -0000 cpghost wrote: > > > > > I always use "dump -L" to dump a live filesystem. > > > > > However, when I restore the dump, I sometimes get messages like > > > > > "foo.txt (inode 12345) not found on tape" or > > > > > "expected next file 12345, got 23456" > > > > > > > > > > I thought this should _never_ happen when dumping a snapshot. > > > > > > > > > > What is it? > > > > > > > > Does nobody know the answer, or am I the only one experiencing the > > > > problem? > > > > > > I don't know the answer, but I get essentially the > > > same behaviour. I have never seen any data loss, > > > > I gave an example below. The file "wins.dat" was not dumped. It is > > indeed missing from the tape. > > > > If this is not a data loss, what is it then? > > > > [root@big ~] restore -b64 -rN > > ./spool/samba.lock/wins.dat: (inode 2829098) not found on tape > > expected next file 267, got 4 > > expected next file 2828988, got 2828987 > > Uh-oh :-(. I have no idea how the code works, but just a wild guess: > what happens when a file is being created and a snapshot taken at the > same time? I would very much like to know that. Creating a snapshot can take several minutes on a large modern HDD. Many files can be changed during those minutes. > Isn't there a tiny window between inode creation and > directory update? Or is file creation an atomic operation w.r.t. > snapshots and dump? -- Victor Sudakov, VAS4-RIPE, VAS47-RIPN sip:sudakov@sibptus.tomsk.ru