From owner-freebsd-fs@freebsd.org Wed Apr 1 14:10:16 2020 Return-Path: Delivered-To: freebsd-fs@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 538902BCE9C for ; Wed, 1 Apr 2020 14:10:16 +0000 (UTC) (envelope-from mike@sentex.net) Received: from pyroxene2a.sentex.ca (pyroxene19.sentex.ca [IPv6:2607:f3e0:0:3::19]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (2048 bits) client-digest SHA256) (Client CN "pyroxene.sentex.ca", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 48sp4F69Vqz3C6p for ; Wed, 1 Apr 2020 14:10:05 +0000 (UTC) (envelope-from mike@sentex.net) Received: from [IPv6:2607:f3e0:0:4:2ca4:3b08:a9aa:a9d4] ([IPv6:2607:f3e0:0:4:2ca4:3b08:a9aa:a9d4]) by pyroxene2a.sentex.ca (8.15.2/8.15.2) with ESMTPS id 031E9tGd005394 (version=TLSv1.3 cipher=TLS_AES_128_GCM_SHA256 bits=128 verify=NO); Wed, 1 Apr 2020 10:09:55 -0400 (EDT) (envelope-from mike@sentex.net) Subject: Re: zfs promote To: Martin Simmons Cc: freebsd-fs@freebsd.org References: <202004011102.031B2an5008896@higson.cam.lispworks.com> From: mike tancsa Autocrypt: addr=mike@sentex.net; keydata= mQENBFywzOMBCACoNFpwi5MeyEREiCeHtbm6pZJI/HnO+wXdCAWtZkS49weOoVyUj5BEXRZP xflV2ib2hflX4nXqhenaNiia4iaZ9ft3I1ebd7GEbGnsWCvAnob5MvDZyStDAuRxPJK1ya/s +6rOvr+eQiXYNVvfBhrCfrtR/esSkitBGxhUkBjOti8QwzD71JVF5YaOjBAs7jZUKyLGj0kW yDg4jUndudWU7G2yc9GwpHJ9aRSUN8e/mWdIogK0v+QBHfv/dsI6zVB7YuxCC9Fx8WPwfhDH VZC4kdYCQWKXrm7yb4TiVdBh5kgvlO9q3js1yYdfR1x8mjK2bH2RSv4bV3zkNmsDCIxjABEB AAG0HW1pa2UgdGFuY3NhIDxtaWtlQHNlbnRleC5uZXQ+iQFUBBMBCAA+FiEEmuvCXT0aY6hs 4SbWeVOEFl5WrMgFAlywzOYCGwMFCQHhM4AFCwkIBwIGFQoJCAsCBBYCAwECHgECF4AACgkQ eVOEFl5WrMhnPAf7Bf+ola0V9t4i8rwCMGvzkssGaxY/5zNSZO9BgSgfN0WzgmBEOy/3R4km Yn5KH94NltJYAAE5hqkFmAwK6psOqAR9cxHrRfU+gV2KO8pCDc6K/htkQcd/mclJYpCHp6Eq EVJOiAxcNaYuHZkeMdXDuvvI5Rk82VHk84BGgxIqIrhLlkguoPbXOOa+8c/Mpb1sRAGZEOuX EzKNC49+GS9gKW6ISbanyPsGEcFyP7GKMzcHBPf3cPrewZQZ6gBoNscasL6IJeAQDqzQAxbU GjO0qBSMRgnLXK7+DJlxrYdHGXqNbV6AYsmHJ6c2WWWiuRviFBqXinlgJ2FnYebZPAfWibkB DQRcsMzkAQgA1Dpo/xWS66MaOJLwA28sKNMwkEk1Yjs+okOXDOu1F+0qvgE8sVmrOOPvvWr4 axtKRSG1t2QUiZ/ZkW/x/+t0nrM39EANV1VncuQZ1ceIiwTJFqGZQ8kb0+BNkwuNVFHRgXm1 qzAJweEtRdsCMohB+H7BL5LGCVG5JaU0lqFU9pFP40HxEbyzxjsZgSE8LwkI6wcu0BLv6K6c Lm0EiHPOl5G8kgRi38PS7/6s3R8QDsEtbGsYy6O82k3zSLIjuDBwA9GRaeigGppTxzAHVjf5 o9KKu4O7gC2KKVHPegbXS+GK7DU0fjzX57H5bZ6komE5eY4p3oWT/CwVPSGfPs8jOwARAQAB iQE8BBgBCAAmFiEEmuvCXT0aY6hs4SbWeVOEFl5WrMgFAlywzOQCGwwFCQHhM4AACgkQeVOE Fl5WrMhmjQf/dBCjAVn1J0GzSsHiLvSAQz1cchbdy8LD0Tnpzjgp5KLU7sNojbI8vqt4yKAi cayI88j8+xxNXPMWM4pHELuUuVHS5XTpHa/wwulUtI5w/zyKlUDsIvqTPZLUEwH7DfNBueVM WyNaIjV2kxSmM8rNMC+RkgyfbjGLCkmWsMRVuLIUYpl5D9WHmenUbiErlKU2KvEEXEg/aLKq 3m/AdM9RAYsP9O4l+sAZEfyYoNJzDhTZMzn/9Q0uFPLK9smDQh4WBTFaApveVJPHRKmHPoNF Xxj+yScYdQ4SKH34WnhNSELvnZQ3ulH5tpASmm0w+GxfZqSc8+QCwoKtBRDUxoE56A== Message-ID: <42019eac-4211-8265-e73e-d3b418b870fe@sentex.net> Date: Wed, 1 Apr 2020 10:09:55 -0400 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <202004011102.031B2an5008896@higson.cam.lispworks.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Content-Language: en-US X-Rspamd-Queue-Id: 48sp4F69Vqz3C6p X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org; dkim=none; dmarc=none; spf=pass (mx1.freebsd.org: domain of mike@sentex.net designates 2607:f3e0:0:3::19 as permitted sender) smtp.mailfrom=mike@sentex.net X-Spamd-Result: default: False [-2.71 / 15.00]; ARC_NA(0.00)[]; NEURAL_HAM_MEDIUM(-1.00)[-1.000,0]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; R_SPF_ALLOW(-0.20)[+ptr]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; MIME_GOOD(-0.10)[text/plain]; HFILTER_HELO_IP_A(1.00)[pyroxene2a.sentex.ca]; DMARC_NA(0.00)[sentex.net]; HFILTER_HELO_NORES_A_OR_MX(0.30)[pyroxene2a.sentex.ca]; TO_MATCH_ENVRCPT_SOME(0.00)[]; RCPT_COUNT_TWO(0.00)[2]; IP_SCORE(-1.71)[ipnet: 2607:f3e0::/32(-4.92), asn: 11647(-3.53), country: CA(-0.09)]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:11647, ipnet:2607:f3e0::/32, country:CA]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_TLS_ALL(0.00)[]; RCVD_COUNT_TWO(0.00)[2] X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 01 Apr 2020 14:10:16 -0000 On 4/1/2020 7:02 AM, Martin Simmons wrote: >>>>>> On Tue, 31 Mar 2020 15:32:53 -0400, mike tancsa said: >> Hi, >> >>     While doing some VM tests, I was making heavy use of clones from my >> zfs server.  (clones are a super cool handy feature!)... However, when >> we went live, I accidentally used a clone as the production file >> system. > I suggest giving some more details about your end goal. > > What was the intended file system structure (i.e. if you had not used a > clone)? We use zrepl to manage replication / backups. It keeps a defined amount of local snapshots (a days worth), but has much more on the remote server.  As this file system changes a lot, I dont want to eatup local fast storage by keeping an increasingly older and divergent snapshot around on the main file server. > > Were you intending to keep both nfs3zroot/cyclenet and nfs3zroot/cyclenetlive? No, just nfs3zroot/cyclenetlive   Now, I cannot delete those old snapshots. > Why do you want to delete the old snapshots? Is that multiple snapshots or > just @clean3? The file system will diverge significantly over time from that original snapshot and will take up more and more space which I dont want locally. > Not quite. Beware this from the documentation: > > "The clone parent-child dependency relationship is reversed, so that the > origin file system becomes a clone of the specified file system." > > and > > "The snapshot that was cloned, and any snapshots previous to this snapshot, > are now owned by the promoted clone." > > Therefore doing zfs promote nfs3zroot/cyclenetlive will cause > nfs3zroot/cyclenet to become a clone of nfs3zroot/cyclenetlive@clean3. If you > then want to destroy nfs3zroot/cyclenetlive@clean3, you will first need to > destroy nfs3zroot/cyclenet. Hmm, I am trying to get my head around this. I should first simulate this in a test environment of course.  What you wrote however seems reversed, but perhaps my perspective is backwards to what is written ? ie Originally I did a zfs clone nfs3zroot/cyclenet@clean3 nfs3zroot/cyclenetlive so I read that as I made a clone called cyclenetlive of the snapshot nfs3zroot/cyclenet@clean3 ? So if promote reverses that, so nfs3zroot/cyclenet@clean3 becomes a clone of nfs3zroot/cyclenetlive ?  so I can then delete nfs3zroot/cyclenet@clean3 ? > > >> Also, how much impact on the disk IO will the promote command have ? Is >> it long like a scrub, or quick like a snapshot ? > It is much more like a snapshot than a scrub. Thank you for the help!     ---Mike > > __Martin >