From owner-freebsd-questions@FreeBSD.ORG Wed Jan 26 22:00:48 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 B6CA910656C8 for ; Wed, 26 Jan 2011 22:00:48 +0000 (UTC) (envelope-from dan@dan.emsphone.com) Received: from email2.allantgroup.com (email2.emsphone.com [199.67.51.116]) by mx1.freebsd.org (Postfix) with ESMTP id 5B8008FC0C for ; Wed, 26 Jan 2011 22:00:47 +0000 (UTC) Received: from dan.emsphone.com (dan.emsphone.com [199.67.51.101]) by email2.allantgroup.com (8.14.4/8.14.4) with ESMTP id p0QM0jpx056258 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 26 Jan 2011 16:00:45 -0600 (CST) (envelope-from dan@dan.emsphone.com) Received: from dan.emsphone.com (smmsp@localhost [127.0.0.1]) by dan.emsphone.com (8.14.4/8.14.4) with ESMTP id p0QM0jYR061487 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 26 Jan 2011 16:00:45 -0600 (CST) (envelope-from dan@dan.emsphone.com) Received: (from dan@localhost) by dan.emsphone.com (8.14.4/8.14.4/Submit) id p0QM0jDY061486; Wed, 26 Jan 2011 16:00:45 -0600 (CST) (envelope-from dan) Date: Wed, 26 Jan 2011 16:00:45 -0600 From: Dan Nelson To: Christer Solskogen Message-ID: <20110126220045.GO75125@dan.emsphone.com> References: <4D3FDE82.4000105@mail.zedat.fu-berlin.de> <20110126195800.GM75125@dan.emsphone.com> <20110126204233.GN75125@dan.emsphone.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-OS: FreeBSD 8.2-PRERELEASE User-Agent: Mutt/1.5.21 (2010-09-15) X-Virus-Scanned: clamav-milter 0.96.4 at email2.allantgroup.com X-Virus-Status: Clean X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.6 (email2.allantgroup.com [199.67.51.78]); Wed, 26 Jan 2011 16:00:45 -0600 (CST) X-Scanned-By: MIMEDefang 2.68 on 199.67.51.78 Cc: "O. Hartmann" , 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 22:00:48 -0000 In the last episode (Jan 26), Christer Solskogen said: > 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. We may have to defer back to Oliver to see exactly how his disks are set up ("zpool status pool1" and "pool2" would be nice), but if he did two "zpool add" commands, he has two independant vdevs in one zpool, and he can mirror each of them with a "zpool attach" command. ZFS doesn't have a "stripe" vdev type. -- Dan Nelson dnelson@allantgroup.com