From owner-freebsd-stable@FreeBSD.ORG Sat Jul 24 02:25:22 2010 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 0F5A7106564A for ; Sat, 24 Jul 2010 02:25:22 +0000 (UTC) (envelope-from fjwcash@gmail.com) Received: from mail-iw0-f182.google.com (mail-iw0-f182.google.com [209.85.214.182]) by mx1.freebsd.org (Postfix) with ESMTP id CB1A18FC08 for ; Sat, 24 Jul 2010 02:25:21 +0000 (UTC) Received: by iwn35 with SMTP id 35so1009202iwn.13 for ; Fri, 23 Jul 2010 19:25:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:in-reply-to :references:date:message-id:subject:from:to:content-type :content-transfer-encoding; bh=L14ESZwOAQ0TmYWIE9q68hm+kosuFSpGhOnnWgorcu0=; b=PsXYkqp8H8uwoh/Al0bm3poDHj+TjHWAA45q7sSrB46axgtUg4n4FSBEjmji+iyhGU +Mbz21TL0JYMnl4Rd3shMt1xBxO+PE6eLxjHgg5W+AWn/GWpPm4TnS6E6keutWTi2WWZ cgwQodztIZR0crw2sR6WWUyqp5ibJwS1C4sz0= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:content-transfer-encoding; b=HEgsuufTfVpQrV/0jfxiU1u0ZeOLgzD03szCEM+QqPIONbZkS6cn+r9lPUwtb55Gdf 23CC+mmTWc3EpIM85GBaYCLfyncaLwkH/sglogDbBea3qb91TitnafAoCUitiJUaVzmg kxlMBHQmjDSsFL8Ur021Bl9PETsEti8f++kFQ= MIME-Version: 1.0 Received: by 10.231.157.207 with SMTP id c15mr4419295ibx.143.1279938321143; Fri, 23 Jul 2010 19:25:21 -0700 (PDT) Received: by 10.231.161.208 with HTTP; Fri, 23 Jul 2010 19:25:20 -0700 (PDT) In-Reply-To: <4C4A42D5.7080805@langille.org> References: <4C47B57F.5020309@langille.org> <4C48E695.6030602@langille.org> <718046944.20100723032259@nitronet.pl> <4C4A42D5.7080805@langille.org> Date: Fri, 23 Jul 2010 19:25:20 -0700 Message-ID: From: Freddie Cash To: freebsd-stable@freebsd.org Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Subject: Re: Using GTP and glabel for ZFS arrays X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 24 Jul 2010 02:25:22 -0000 On Fri, Jul 23, 2010 at 6:33 PM, Dan Langille wrote: > Pawell and I had an online chat about part of my strategy. =C2=A0To be cl= ear: > > I have a 5x2TB raidz1 array. > > I have 2x2TB empty HDD > > My goal was to go to raidz2 by: > - copy data to empty HDD > - redo the zpool to be raidz2 > - copy back the data > - add in the two previously empty HDD to the zpol > > I now understand that after a raidz array has been created, you can't add= a > new HDD to it. =C2=A0I'd like to, but it sounds like you cannot. > > "It is not possible to add a disk as a column to a RAID-Z, RAID-Z2, or > RAID-Z3 vdev." http://en.wikipedia.org/wiki/ZFS#Limitations > > So, it seems I have a 5-HDD zpool and it's going to stay that way. You can fake it out by using sparse files for members of the new raidz2 vdev (when creating the vdev), then offline the file-based members so that you are running a degraded pool, copy the data to the pool, then replace the file-based members with physical harddrives. I've posted a theoretical method for doing so here: http://forums.freebsd.org/showpost.php?p=3D93889&postcount=3D7 It's theoretical as I have not investigated how to create sparse files on FreeBSD, nor have I done this. It's based on several posts to the zfs-discuss mailing list where several people have done this on OpenSolaris. --=20 Freddie Cash fjwcash@gmail.com