From owner-freebsd-questions@freebsd.org Mon Jan 15 15:09:53 2018 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id D8320EB30E7; Mon, 15 Jan 2018 15:09:53 +0000 (UTC) (envelope-from dweimer@dweimer.net) Received: from webmail.dweimer.net (24-240-198-186.static.stls.mo.charter.com [24.240.198.186]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "dweimer.net", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 7CC687AB18; Mon, 15 Jan 2018 15:09:52 +0000 (UTC) (envelope-from dweimer@dweimer.net) Received: from www.dweimer.net (opnsense.dweimer.local [10.9.5.1]) (authenticated bits=0) by webmail.dweimer.net (8.15.2/8.15.2) with ESMTPSA id w0FEwpfq080603 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Mon, 15 Jan 2018 08:58:51 -0600 (CST) (envelope-from dweimer@dweimer.net) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=dweimer.net; s=2017.01.31; t=1516028331; bh=cyREgycBcxsh7r6qKK2lLFopTSEaahf2WjxCybRSm/g=; h=Date:From:To:Cc:Subject:Reply-To:In-Reply-To:References; b=tsuelBLD/gwgAA5nyESQUkkg7I3iTNQHcOpPiqZVoItybBja+DLZIcjI+YdpJW/Ba GIwICD/Mw1obKzuaAsQPEk4U89gqd1bthqVd4iAGYOm4WCR28o4WFP26MvH3RPPLI0 nNhEPqvZoWGaV0zQk6nRTdJSM9GOqvj3QNELmuPB7y02z5QcTC+1NY+cUM9plh0EAB jn/lqzimNRYe0wmJsNFJlgr/dCJpzQ/ZQ4PbTPrMDxT86EPtHm9S+Q+hMHTR+ya5xr /3n2AJWgmjM3F8ap/rfdrZBWRKpjkMXWJ6c+B8+yY4qgKGg6l+vRkXecseGrMTK8NX 1Akrd1mjutwNg== MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Mon, 15 Jan 2018 08:58:46 -0600 From: "Dean E. Weimer" To: Victor Sudakov Cc: Manish Jain , freebsd-questions@freebsd.org, owner-freebsd-questions@freebsd.org Subject: Re: Dualboot and ZFS Organization: dweimer.net Reply-To: dweimer@dweimer.net Mail-Reply-To: dweimer@dweimer.net In-Reply-To: <20180115144747.GA65526@admin.sibptus.transneft.ru> References: <20180115051308.GA45168@admin.sibptus.transneft.ru> <20180115125241.GB60956@admin.sibptus.transneft.ru> <20180115144747.GA65526@admin.sibptus.transneft.ru> Message-ID: <9bb8ddb71ab9ef1775130be761063203@dweimer.net> X-Sender: dweimer@dweimer.net User-Agent: Roundcube Webmail/1.3.4 X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.25 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 15 Jan 2018 15:09:54 -0000 On 2018-01-15 8:47 am, Victor Sudakov wrote: > Manish Jain wrote: >> >> > Sorry if my question was misleading, I did not mean converting the >> > existing system from UFS to ZFS at ada0s3. Suppose ada0s3 is an unused >> > slice, I can probably create a zpool thereon. But a few questions >> > remain: >> > >> > 1. Can I install a root-on-zfs system on ada0s3 with bsdinstall? I >> > suppose not? >> >> That's right. You cannot install ZFS onto an MBR slice. ZFS by default >> needs an entire disk, partitioned GPT. > > However, later you suggest it's possible to install freebsd-zfs on a > BSD slice. How is that? > >> >> > Why are you creating a zpool within a BSD "a" partition, and not in >> > da0s1 directly? I have never seen such a configuration. Is it even >> > possible to set the "freebsd-zfs" type on a BSD partition? >> >> I presume you are using MBR partitioning. Under MBR, freebsd slices >> are >> always nested. The slice contains partitions denoted with a, b and so >> on. >> >> I do not think it is viable to set freebsd-zfs on an MBR slice. It >> just >> will not work. ZFS needs an entire disk. If you wish to install on an >> MBR slice, you must use rsync after installing freebsd-UFS. > > Do you mean to say it's viable to install freebsd-zfs on ada0s3a but > not viable on ada0s3 ? I don't see logic here. It can be installed on a partition, but it has to be GPT, not MBR, from one of my servers I have this GPT partition setup. # gpart show -p => 40 1953525088 ada0 GPT (932G) 40 1024 ada0p1 freebsd-boot (512K) 1064 33554432 ada0p2 freebsd-swap (16G) 33555496 1919969624 ada0p3 freebsd-zfs (916G) 1953525120 8 - free - (4.0K) ZFS is designed to use a full raw disk, but you need to have a boot partition, and in this case I setup swap as well outside of ZFS. This server never hits swap though, so I don't have any real world metrics on whether or not this is better that running swap on a zvol inside of ZFS. There is a second drive duplicating this and GEOM mirror used for the swap, along with ZFS mirror for redundancy and a second boot partition. -- Thanks, Dean E. Weimer http://www.dweimer.net/