From owner-freebsd-questions@FreeBSD.ORG Sat Aug 18 10:26:45 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 3DEEF16A418 for ; Sat, 18 Aug 2007 10:26:45 +0000 (UTC) (envelope-from jhary@unsane.co.uk) Received: from unsane.co.uk (unknown [IPv6:2001:470:1f01:ffff::121]) by mx1.freebsd.org (Postfix) with ESMTP id A219D13C467 for ; Sat, 18 Aug 2007 10:26:44 +0000 (UTC) (envelope-from jhary@unsane.co.uk) Received: from crab.unsane.co.uk ([10.0.0.111]) (authenticated bits=0) by unsane.co.uk (8.14.0/8.14.0) with ESMTP id l7IAOlm4059361 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sat, 18 Aug 2007 11:24:48 +0100 (BST) (envelope-from jhary@unsane.co.uk) Message-ID: <46C6C935.1090309@unsane.co.uk> Date: Sat, 18 Aug 2007 11:25:57 +0100 From: Vince User-Agent: Thunderbird 2.0.0.6 (X11/20070803) MIME-Version: 1.0 To: Victor Sudakov , User Questions References: <20070724115401.GA1355@admin.sibptus.tomsk.ru> <20070724134431.GA57022@epia-2.farid-hajji.net> <20070807113147.O28568@wojtek.tensor.gdynia.pl> <20070818071753.GA44252@admin.sibptus.tomsk.ru> In-Reply-To: <20070818071753.GA44252@admin.sibptus.tomsk.ru> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: 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: Sat, 18 Aug 2007 10:26:45 -0000 Victor Sudakov wrote: > Colleagues, > > Right now I am watching a dump: > > [root@admin ~] dump -b64 -5Lau /home > DUMP: Connection to big.sibptus.tomsk.ru established. > DUMP: Date of this level 5 dump: Sat Aug 18 14:02:16 2007 > DUMP: Date of last level 0 dump: Sun Aug 12 11:10:56 2007 > DUMP: Dumping snapshot of /dev/ad0s2f (/home) to /dev/nsa0 on host big > DUMP: mapping (Pass I) [regular files] > DUMP: mapping (Pass II) [directories] > DUMP: estimated 3249348 tape blocks. > > at the same moment: > > [root@admin ~] snapinfo -v /home > /dev/ad0s2f mounted on /home > no snapshots found > [root@admin ~] ll /home/.snap/ > total 0 > [root@admin ~] > > > Is this normal? Does it mean that dump is not really dumping a > snapshot though it says it is? > man dump (the section regarding -L) says "The snapshot is unlinked as soon as the dump starts, and is thus removed when the dump is complete." What this means to you is that the snapshot is only visible on the file system for as long as it takes dump to start reading from it, dump will have an open filehandle to the snapshot so it can be unlinked from the filesystem and as soon as dump closed its handle then the snapshot is removed. Similar to when you delete a large logfile a program has open and forget to HUP/stop/restart the program, the logfile's diskspace isnt released until the the program closes its file handle. Vince