From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BA753C3A5A9 for ; Wed, 4 Sep 2019 21:04:13 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9CCB720674 for ; Wed, 4 Sep 2019 21:04:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730612AbfIDVEM (ORCPT ); Wed, 4 Sep 2019 17:04:12 -0400 Received: from relay1-d.mail.gandi.net ([217.70.183.193]:44591 "EHLO relay1-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727900AbfIDVEM (ORCPT ); Wed, 4 Sep 2019 17:04:12 -0400 X-Originating-IP: 88.191.131.7 Received: from [192.168.1.167] (unknown [88.191.131.7]) (Authenticated sender: swami@petaramesh.org) by relay1-d.mail.gandi.net (Postfix) with ESMTPSA id 4C143240003; Wed, 4 Sep 2019 21:04:09 +0000 (UTC) Subject: Re: Cloning / getting a full backup of a BTRFS filesystem To: Chris Murphy References: <7d044ff7-1381-91c8-2491-944df8315305@petaramesh.org> <20190904140444.GH31890@pontus.sran> <20190904202012.GF2488@savella.carfax.org.uk> Cc: Hugo Mills , Piotr Szymaniak , Andrei Borzenkov , Linux BTRFS Mailinglist From: =?UTF-8?Q?Sw=c3=a2mi_Petaramesh?= Openpgp: preference=signencrypt Autocrypt: addr=swami@petaramesh.org; prefer-encrypt=mutual; keydata= xsDiBEP8C/QRBADPiYmcQstlx+HdyR2FGH+bDgRZ0ZJBAx6F0OPW+CmIa6tlwdhSFtCTJGcw eqCgSKqzLS+WBd6qknpGP3D2GOmASt+Juqnl+qmX8F/XrkxSNOVGGD0vkKGX4H5uDwufWkuV 7kD/0VFJg2areJXx5tIK4+IR0E0O4Yv6DmBPwPgNUwCg0OdUy9lbCxMmshwJDGUX2Y/hiDsD /3YTjHYH2OMTg/5xXlkQgR4aWn8SaVTG1vJPcm2j2BMq1LUNklgsKw7qJToRjFndHCYjSeqF /Yk2Cbeez9qIk3lX2M59CTwbHPZAk7fCEVg1Wf7RvR2i4zEDBWKd3nChALaXLE3mTWOE1pf8 mUNPLALisxKDUkgyrwM4rZ28kKxyA/960xC5VVMkHWYYiisQQy2OQk+ElxSfPz5AWB5ijdJy SJXOT/xvgswhurPRcJc+l8Ld1GWKyey0o+EBlbkAcaZJ8RCGX77IJGG3NKDBoBN7fGXv3xQZ mFLbDyZWjQHl33wSUcskw2IP0D/vjRk/J7rHajIk+OxgbuTkeXF1qwX2yc0oU3fDom1pIFBl dGFyYW1lc2ggPHN3YW1pQHBldGFyYW1lc2gub3JnPsJ+BBMRAgA+AhsDAh4BAheABQsJCAcC BhUKCQgLAgQWAgMBFiEEzB/joG05+rK5HJguL8JcHZB24y4FAl0Cdr0FCSJsbEkACgkQL8Jc HZB24y7PrwCeIj82AsMnwgOebV274cWEyR/yaDsAn25VN/Hw+yzkeXWAn5uIWJ+ZsoZkzsNN BEP8DFwQEAC77CwwyVuzngvfFTx2UzFwFOZ25osxSYE1Hpw249kbeK09EYbvMYzcWR34vbS0 DhxqwJYH9uSuMZf/Jp4Qa/oYN4x4ZMeOGc5+BdigcetQQnZkIpMaCdFm6HK/A4aqCjqbPpvF 3Mtd4CXcl1v94pIWq/n9JrLNclUA7rWnVKkPDqJ8WaxzDWm2YH9l1H+K+JbU/ow+Rk+y5xqp jL3XpOsVqf34RQhFUyCoysvvxH8RdHAeKfWTf5x6P8jOvxB6XwOnKkX91kC2N7PzoDxY7llY Uvy+ehrVVpaKLJ1a1R2eaVIHTFGO//2ARn6g4vVPMB93FLNR0BOGzEXCnnJKO5suw9Njv/aL bdnVdDPt9nc1yn3o8Bx/nZq1asX3zo/PnMz4Up24l6GrakJFMBZybX/KxA0CXDK6Rq4HSphI y/+v0I27FiQm7oT4ykiKnfFuh16NWM8rPV0UQgBLxSBoz327bUpsRuSrYh/oYBbE6p5KYHlB Acpix7wQ61OdUihBX73/AAx0Gd53fc0d4AYeKy4JXMl2uP2aiIvBeBaOKY5tzIq9gnL5K6rr xt4PSeONoLdVo8m8OyYeao1zvpgeNZ6FJ+VCYGBtsZEYIi80Ez5V0PpgAh7kSY1xbimDqKQx A/Jq2Q7sXBCdUeHN5cDgOZLKoJRvat/rhNaCSgUNfhUc2wADBRAAskb9Eolxs20NCfs424b3 /NRI7SVn9W2hXvI61UYfs19lfScnn9YfmiN7IdB2cLCE6OiAbSsK3Aw8HDnEc0AdylVNOiIK su7C4+CW6HKMyIUm1q2qv8RwW3K8eE8+S4+4/5k+38T39BlC3HcLSxS9vfgqmF6mF6VeD5Mn DDbrm7G06UFm1Eh5PKFSzYKZ4i9rD9R4ivDCxRBT9Cibw36iigdp14z87/Qq/NoFe8j9zrbs 3/3XZ22NxS0G8aNi0ejgDeYVRUUudBXK7zjV/pJDS4luB9iOiblysJmdKI3EegHlAcapTASn qsJ42O/Uv9jdSPPruZrMbeRKILqOl/YtI0orHGW/UzMYf/vbYWZ82azkPQqKDZF3Tb3h6ZHt csifD/J9IN7xh71aPf8ayIAus1AtPFtPUTjIJXqXIvAlNcDpaEpxn8xxcbVdcRBU/odASwsX IPdz8/HV5esod/QhR6/16kkKyOJNF5M/qC3PLur8Zu4iRu8EPiPr6vTAjhLrfXbQycuVc4CV c+hGlyYSW0xFaT+XF/4d+KZirsu07P5w/OCu+oRhH4StCOz58KrtuaX1dK5nLk6XkM4nKZhC 7kmpnPqS6BkdJngkozuKQZMJahIvFglag90xgLrOl5MtO55yr/0j4S4a8GxTkVs70GttcMKN TYaSBqmVw+0A3ILCZgQYEQIAJgIbDBYhBMwf46BtOfqyuRyYLi/CXB2QduMuBQJdAnbyBQki bGwWAAoJEC/CXB2QduMur1wAn1X3FcsmMdhMfiYwXw7LVw4FAIeWAJ9kLGer22WFWR2z2iU7 BtUAN08OPA== Message-ID: <5b5cc1fd-1e68-53c5-97bd-876c5cf08683@petaramesh.org> Date: Wed, 4 Sep 2019 23:04:08 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: fr-FR Content-Transfer-Encoding: 8bit Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org Hello and thanks for the replies all, Le 04/09/2019 à 22:48, Chris Murphy a écrit : > If you want an exact copy, including all of the exact UUIDs, yes. No I don"t really care about the UUIDs, and it's the only thing I don't care about. My use case is rather taking a full and complete copy of my NAS BTRFS RAID-5 storage space onto an external, eventually big, disk, or some other RAID combination in case something would go wrong - in a way that I could get everything backed up and restored easily. So far and for years I found BTRFS to be extremely reliable and resilient in all configurations, but I've had several issues with recent 5.1 and 5.2 kernels on several machines recently . My NAS holds a number of subvols for many different purposes, most of them contains a hosts of RO snaphots made either manually or automatically using snapper, and everything is offline-deduped using bees (as there is a *lot* of redundant copies of the same files in different subvols and structures). Of course I cannot just “dd” as I don't start from a single device but a BTRFS RAID, and I'm afraid that any manual scheme that I could think of would break deduplication and thus result in a huge output that wouldn't fit any device I could think of. So the question reslly is : How could I backup a complex BTRFS volume to another but differently (physically) organized volume keeping the complete structure and being able to restore it preferably in a single operation. If the answer is « There's no way it can be done » then it is really badly annoying... ॐ -- Swâmi Petaramesh PGP 9076E32E