From owner-freebsd-questions@FreeBSD.ORG Sun Sep 10 18:26:51 2006 Return-Path: X-Original-To: freebsd-questions@freebsd.org 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 29BFF16A403 for ; Sun, 10 Sep 2006 18:26:51 +0000 (UTC) (envelope-from bob@tania.servebbs.org) Received: from mail2.panix.com (mail2.panix.com [166.84.1.73]) by mx1.FreeBSD.org (Postfix) with ESMTP id A6D6543D46 for ; Sun, 10 Sep 2006 18:26:50 +0000 (GMT) (envelope-from bob@tania.servebbs.org) Received: from mailspool3.panix.com (mailspool3.panix.com [166.84.1.78]) by mail2.panix.com (Postfix) with ESMTP id E7CB69D850 for ; Sun, 10 Sep 2006 14:26:49 -0400 (EDT) Received: from tania.servebbs.org (pool-71-247-27-125.nycmny.east.verizon.net [71.247.27.125]) by mailspool3.panix.com (Postfix) with ESMTP id 06DB3D908E0 for ; Sun, 10 Sep 2006 14:26:47 -0400 (EDT) From: Bob Organization: TamaraB To: freebsd-questions@freebsd.org Date: Sun, 10 Sep 2006 14:26:51 -0400 User-Agent: KMail/1.9.1 MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200609101426.52892.bob@tania.servebbs.org> Subject: SnapShot Magic 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: Sun, 10 Sep 2006 18:26:51 -0000 Hi: Last week I installed all the bits and pieces to do automatic snapshots, and allow regular users to retreive lost/corrupted data from hours, days, and weeks ago. It was all quite simple, and logical. Now that it has been running for several days I have a few questions. How can this be?: $ snapshot list /usr Filesystem User User% Snap Snap% Snapshot /usr 11399MB 37.1% 116MB 0.4% daily.0 /usr 11399MB 37.1% 136MB 0.4% daily.1 /usr 11399MB 37.1% 25MB 0.1% hourly.0 /usr 11399MB 37.1% 28MB 0.1% hourly.1 /usr 11399MB 37.1% 117MB 0.4% hourly.2 /usr 11399MB 37.1% 120MB 0.4% hourly.3 How can /usr:hourly.0 be 25MB, and /usr:hourly.3 be 120MB ??? What's even more mystifying is this: $ ls -al /usr/.snap total 558260 drwxrwxr-x 2 root operator 512 Sep 10 12:00 . drwxr-xr-x 20 root wheel 512 Aug 23 13:55 .. -r-------- 1 root operator 33282639248 Sep 10 14:15 daily.0 -r-------- 1 root operator 33282639248 Sep 10 14:03 daily.1 -r-------- 1 root operator 33282639248 Sep 10 14:15 hourly.0 -r-------- 1 root operator 33282639248 Sep 10 14:15 hourly.1 -r-------- 1 root operator 33282639248 Sep 10 14:15 hourly.2 -r-------- 1 root operator 33282639248 Sep 10 14:03 hourly.3 /usr is a 33GB HW/Raid partition, how can it possibly hold 6 33GB snapshots??? If I mount each one of these, they all report to df that they are indeed 33BB file systems! How is this magic achieved? Is there a doc somewhere with an explaination? TIA Bob