From owner-freebsd-questions@FreeBSD.ORG Wed Jan 26 21:57:27 2011 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 3D160106564A for ; Wed, 26 Jan 2011 21:57:27 +0000 (UTC) (envelope-from ohartman@mail.zedat.fu-berlin.de) Received: from outpost1.zedat.fu-berlin.de (outpost1.zedat.fu-berlin.de [130.133.4.66]) by mx1.freebsd.org (Postfix) with ESMTP id E7AFE8FC0A for ; Wed, 26 Jan 2011 21:57:26 +0000 (UTC) Received: from inpost2.zedat.fu-berlin.de ([130.133.4.69]) by outpost1.zedat.fu-berlin.de (Exim 4.69) with esmtp (envelope-from ) id <1PiDMj-0001Wb-0y>; Wed, 26 Jan 2011 22:57:25 +0100 Received: from e178018247.adsl.alicedsl.de ([85.178.18.247] helo=thor.walstatt.dyndns.org) by inpost2.zedat.fu-berlin.de (Exim 4.69) with esmtpsa (envelope-from ) id <1PiDMi-0000tI-TZ>; Wed, 26 Jan 2011 22:57:24 +0100 Message-ID: <4D4098C4.6000105@mail.zedat.fu-berlin.de> Date: Wed, 26 Jan 2011 22:57:24 +0100 From: "O. Hartmann" User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US; rv:1.9.2.13) Gecko/20101218 Lightning/1.0b2 Thunderbird/3.1.7 MIME-Version: 1.0 To: Christer Solskogen References: <4D3FDE82.4000105@mail.zedat.fu-berlin.de> <20110126195800.GM75125@dan.emsphone.com> <20110126204233.GN75125@dan.emsphone.com> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-15; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: 85.178.18.247 Cc: Dan Nelson , freebsd-questions@freebsd.org Subject: Re: FreeBSD 9/ZFS: Striped Pool (2 disks) migrating to mirror (onto additional disk) X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 26 Jan 2011 21:57:27 -0000 On 01/26/11 21:47, Christer Solskogen wrote: > On Wed, Jan 26, 2011 at 9:42 PM, Dan Nelson wrote: > >> ZFS lets you add and detach mirrors on the fly, since you're not changing >> the capacity of the pool itself. Sure, you're going to lose the contents of >> the large 2TB drive, but that's sort of assumed. You can't convert 4TB of >> non-mirrored disks into 2TB of mirrored disks without losing 2TB of space. >> Just make sure you have less than 2TB total used data on all volumes, and >> copy the data off the 2TB filessytem onto the striped 1+1TB one before >> repartitioning and adding the mirrors. >> >> zpool attach [-f] pool device new_device >> > > The problem is that you cant attach a drive to a vdev that consists of > two striped disks. > All right, I see there is no way without any kind of trade-off. My thinking was simple, I thought since the two physical 1TB disks build one joint pool of 2TB overall capacity, I could simply 'mirror' this pool to another disk of the same capacity. Is there a way to 'send' via ZFS the data of the pool to the backup disk, like a snapshot from one pool to another one? Oliver