From owner-freebsd-virtualization@freebsd.org Tue Aug 7 19:21:00 2018 Return-Path: Delivered-To: freebsd-virtualization@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 3230F10685C1 for ; Tue, 7 Aug 2018 19:21:00 +0000 (UTC) (envelope-from paul.g.webster@googlemail.com) Received: from mail-ua0-x22b.google.com (mail-ua0-x22b.google.com [IPv6:2607:f8b0:400c:c08::22b]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id C3E3A7D3C9 for ; Tue, 7 Aug 2018 19:20:59 +0000 (UTC) (envelope-from paul.g.webster@googlemail.com) Received: by mail-ua0-x22b.google.com with SMTP id i4-v6so17406623uak.0 for ; Tue, 07 Aug 2018 12:20:59 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=S+3oHnxQu3x1ad/RjAdMl1jQYGrpdv+taGWztocZq1o=; b=AxcJrSO2LaVJwJ5gAk3o5zezsH0i4AUqSzX9LuPF6IvnqlWBCIfnreIb/ugWFpCjl+ fwxKz0pcIayydqH4MgH+icz/TOPprl5wHJOlWGegBk7D8fwy3I1Ewgq+0do/0C3s0/Nz jyZjKLXY5y3+Ci+AeqtDZ0Lh8W5zHAjb7n2/bQJ4pKC4yVbK6cBLcM/QjW8i+7FbtYPG 5Lkzd5iPfLLSk/W1YyML25H0LN7IhSv6T7D6RvHTp4JywfCjAj4dIRCPcj27OM1W+saG X2dSXutsxP0RhOdEknZPSSP+g5sI4x4UcyLBaXWddYrWJsXXWHb4o9guFHKzvlIvU8l5 TSXQ== X-Gm-Message-State: AOUpUlHBSaPnMjfb4JFOWjf73e2hg08/um/BKHpec2rGO9qZR5g8HO0F NnUduApWoikdBQONkiNYb15ircL1jOeFe5fwPZibKDSp X-Google-Smtp-Source: AAOMgpcNkQT1MxgvJxUO0863Kw9S/qEiI2KmJ2FBpVpHtEyFrTZ6dRP3wIUtUFSMEE8IMk3qgaeBRfRDK8GrM6/lEfM= X-Received: by 2002:a9f:2266:: with SMTP id 93-v6mr14143484uad.40.1533669658836; Tue, 07 Aug 2018 12:20:58 -0700 (PDT) MIME-Version: 1.0 Received: by 2002:ab0:21ca:0:0:0:0:0 with HTTP; Tue, 7 Aug 2018 12:20:58 -0700 (PDT) In-Reply-To: References: <20180805224205.GB17784@tau1.ceti.pl> <20180807170648.GA1599@tau1.ceti.pl> From: Paul Webster Date: Tue, 7 Aug 2018 20:20:58 +0100 Message-ID: Subject: Re: Seeking advice on virtualization To: Jakub Chromy Cc: "freebsd-virtua." Content-Type: text/plain; charset="UTF-8" X-Content-Filtered-By: Mailman/MimeDel 2.1.27 X-BeenThere: freebsd-virtualization@freebsd.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: "Discussion of various virtualization techniques FreeBSD supports." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 07 Aug 2018 19:21:00 -0000 even cooler you get 'clones' so you can say make a raw/zvol of debian or whatever you like then if you make a snapshot of it and clone it to something else 'debian2' it uses no space until you write/delete/edit something, basically the clone only has diffs. And yes zvols are literally like raw devices, dd style you can infact take a raw image and dd it to a zvol On 7 August 2018 at 19:57, Jakub Chromy wrote: > I was writing about "hard disk file" format, in which a hypervisor >> (i.e. bhyve, kvm, virtualbox) is keeping a disk for emulated >> machine. Wikipedia calls it "img format": >> >> https://en.wikipedia.org/wiki/IMG_(file_format) >> >> Advantage from using this format (as opposed to something like qcow or >> vmhd) is that, in theory (and even in practice) one can boot such >> machine (I mean, virtual machine defined with such "raw" hard drives) >> using any hypervisor. >> > > ZFS ZVOL is a true "raw device" as well... (or at least it did behave like > that for me): > > dd if=/dev/zvol/pool/mypornhubpremiumarchive0 > of=/var/vm/mypornhubpremiumarchive0.raw > > but you get snapshots, zfs send | zfs recv and stuff. > > -- > > > regards / s pozdravem > > > Jakub Chromy > > > CGI Systems div. > ---------------- > CGI CZ s.r.o. > sales@cgi.cz > 775 144 257 > 234 697 102 > www.cgi.cz > > > On 7.8.2018 19:06, Tomasz Rola wrote: > >> On Mon, Aug 06, 2018 at 12:07:13AM +0100, Paul Webster wrote: >> >>> In theory as ZFS works on both linux and BSD you could simply use vdevs >>> and >>> snapshots for easy transport >>> >> Um-hm. >> >> I was writing about "hard disk file" format, in which a hypervisor >> (i.e. bhyve, kvm, virtualbox) is keeping a disk for emulated >> machine. Wikipedia calls it "img format": >> >> https://en.wikipedia.org/wiki/IMG_(file_format) >> >> Advantage from using this format (as opposed to something like qcow or >> vmhd) is that, in theory (and even in practice) one can boot such >> machine (I mean, virtual machine defined with such "raw" hard drives) >> using any hypervisor. Or to put it differently, it is not proprietary >> and is the easiest one to implement, so it is what most probably will >> keep being used years or decades from now (in whatever hypervisor / PC >> emulator of the future day is fashionable). >> >> I believe in the past I have installed an OS (say, FreeDOS) using >> virtualbox and after deciding I would not use virtualbox in a future, >> I started to boot said machine using kvm. Likewise, I believe some >> OSes rejected being installed under certain hypervisor, so one had to >> install them using this other hypervisor and then could happily >> continue to run it under his preferred hypervisor. >> >> All of this made possible thanks to avoiding file formats supported by >> one or only few hypervisors. >> >> Of course there are many hd-file formats and some are supported by >> more than one hypervisor, but the easiest one is raw and in case of >> emergency it can be also mounted as any other block device (always, I >> guess, but I would pay attention to block size mismatch). >> >> > _______________________________________________ > freebsd-virtualization@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-virtualization > To unsubscribe, send any mail to "freebsd-virtualization-unsubs > cribe@freebsd.org" >