From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by finch.gentoo.org (Postfix) with ESMTPS id 8EE0915815E for ; Mon, 12 Feb 2024 08:34:32 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id D03D7E2A21; Mon, 12 Feb 2024 08:34:23 +0000 (UTC) Received: from smtp.CeBiTec.Uni-Bielefeld.DE (smtp.CeBiTec.Uni-Bielefeld.DE [129.70.160.84]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id 273CEE29D3 for ; Mon, 12 Feb 2024 08:34:21 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp.CeBiTec.Uni-Bielefeld.DE (Postfix) with ESMTP id 0E4AFBD063 for ; Mon, 12 Feb 2024 09:34:19 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d= cebitec.uni-bielefeld.de; h=content-transfer-encoding :content-type:content-type:in-reply-to:from:from :content-language:references:subject:subject:user-agent :mime-version:date:date:message-id:received:received; s= 20200306; t=1707726858; bh=4SrieGUoJYSTdC35pcmnD/MNQE6nnn+bjdJBx M0Bmqs=; b=Zk8Q+YM0dBn/NGN++F7vx/oSygdwF4PbeY4tM5QbinnW0C9gqvI6A qEalsV39+EjTyCJz/uUUywxuhCoIk7svTU4YFZsrnsHfMIxelbn/tqVHURE+ye2W hZCTaAfPLhuq9n8+SfwjWGHNoROSJwkvXWu4wj8z559eT+4elkKuew+iXtpvadi6 f7t8rgbaxg4HnssPrQ0DK9TPAMASHmcRany5jAKVSnuWZoaOKnoWW8xSBYMxtTZe KpKxh2/fwqFvF0Ro8JmjTa4/kC/ykBYZwxgJ2y0UUqYtYrO9Sq2+Pe+NyjjMt9bF Aaz1ZyPWOlzNNN5sx0TWe6WEgMRysOHuw== X-Virus-Scanned: amavisd-new at cebitec.uni-bielefeld.de Received: from smtp.CeBiTec.Uni-Bielefeld.DE ([127.0.0.1]) by localhost (smtp.cebitec.uni-bielefeld.de [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id RwQw4QAJMgFt for ; Mon, 12 Feb 2024 09:34:18 +0100 (CET) Message-ID: <416f3775-edf0-28d5-1ef2-e6b87efbd392@cebitec.uni-bielefeld.de> Date: Mon, 12 Feb 2024 09:34:18 +0100 Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org X-Auto-Response-Suppress: DR, RN, NRN, OOF, AutoReply MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.15.1 Subject: Re: [gentoo-user] Don't be like stupid me! To: gentoo-user@lists.gentoo.org References: Content-Language: en-US From: =?UTF-8?Q?Bj=c3=b6rn_Fischer?= In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Archives-Salt: ba58ccbc-28c0-4a44-9240-968a66aef157 X-Archives-Hash: adcabe85afab22b448b5d1136329f611 On 2/11/24 03:14:49, William Kenworthy wrote: [...] >> It occurred to me fairly quickly after that press of RET that I >> could have done well with a COW snapshot facility, something which >> has been discussed at length on another recent thread. I even have >> LVM on my machine for its RAID capabilities. But I've never >> bothered before. I mean "I'm too careful", amn't I? ;-( At least >> I do a weekly backup, though. [...] > No, you don't need a snapshot system - you need a proper backup > system that stores the proper metadata. When I was experimenting > with snapshots (btrfs and moosefs) at different times I lost > everything a few times with filesystem corruption which meant I lost > the snapshots too. > > Snapshots are NOT safe backups - treat them as a convenient copy ... Snapshots are as reliable as the underlying file system. Here at CeBiTec we use snapshots on several PB CephFS and ZFS with great success. And yes, I completely agree with Alan, snapshots would have saved his day as they provide excellent and cost efficient protection against pilot errors. Our users restore lost data from snapshots themselves in seconds, while it usually takes several hours to restore data from tape. Snapshots and tape backups complement each other perfectly and both strategies provide means of protection the other lacks. Cheers Björn