From owner-freebsd-fs@FreeBSD.ORG Wed Jan 23 11:00:32 2013 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by hub.freebsd.org (Postfix) with ESMTP id 2C4CAFBC for ; Wed, 23 Jan 2013 11:00:32 +0000 (UTC) (envelope-from peter@rulingia.com) Received: from vps.rulingia.com (host-122-100-2-194.octopus.com.au [122.100.2.194]) by mx1.freebsd.org (Postfix) with ESMTP id 99CFF986 for ; Wed, 23 Jan 2013 11:00:30 +0000 (UTC) Received: from server.rulingia.com (c220-239-246-167.belrs5.nsw.optusnet.com.au [220.239.246.167]) by vps.rulingia.com (8.14.5/8.14.5) with ESMTP id r0NB0LxN070489 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Wed, 23 Jan 2013 22:00:23 +1100 (EST) (envelope-from peter@rulingia.com) X-Bogosity: Ham, spamicity=0.000000 Received: from server.rulingia.com (localhost.rulingia.com [127.0.0.1]) by server.rulingia.com (8.14.5/8.14.5) with ESMTP id r0NB0GSV078381 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 23 Jan 2013 22:00:16 +1100 (EST) (envelope-from peter@server.rulingia.com) Received: (from peter@localhost) by server.rulingia.com (8.14.5/8.14.5/Submit) id r0NB0Eu9078372; Wed, 23 Jan 2013 22:00:14 +1100 (EST) (envelope-from peter) Date: Wed, 23 Jan 2013 22:00:14 +1100 From: Peter Jeremy To: Mark Felder Subject: Re: RFC: Suggesting ZFS "best practices" in FreeBSD Message-ID: <20130123110014.GL30633@server.rulingia.com> References: <314B600D-E8E6-4300-B60F-33D5FA5A39CF@sarenet.es> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="X0cz4bGbQuRbxrVl" Content-Disposition: inline In-Reply-To: X-PGP-Key: http://www.rulingia.com/keys/peter.pgp User-Agent: Mutt/1.5.21 (2010-09-15) Cc: FreeBSD Filesystems X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 23 Jan 2013 11:00:32 -0000 --X0cz4bGbQuRbxrVl Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 2013-Jan-22 09:26:39 -0600, Mark Felder wrote: >On Tue, 22 Jan 2013 09:04:42 -0600, Warren Block =20 >wrote: > >> I'm a proponent of using various types of labels, but my impression =20 >> after a recent experience was that ZFS metadata was enough to identify = =20 >> the drives even if they were moved around. That is, ZFS bare metadata = =20 >> on a drive with no other partitioning or labels. >> Is that incorrect? > >If you have an enclosure with 48 drives can you be confident which drive = =20 >is failing using only the ZFS metadata? There are two different issues here. ZFS stores metadata on each disk which it uses to determine the pool layout and where that disk fits into that layout. The device pathname is solely used as a hint and ZFS doesn't care how you juggle the disks. OTOH, the sysadmin needs some way of identifying a physical disk based on the logical identifiers that the system provides. This is totally up to the sysadmin and there's no reason why you couldn't write ZFS disklabel numbers on your physical disks in addition to or instead of writing "daX" or the gpart label onto the disk. --=20 Peter Jeremy --X0cz4bGbQuRbxrVl Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (FreeBSD) iEYEARECAAYFAlD/wr4ACgkQ/opHv/APuIfYfgCfVd+wj/su3P64uAemE2L+xpu3 tgoAn3OHxDDSUyqA7DLglR5zEOF+7pOs =6jxg -----END PGP SIGNATURE----- --X0cz4bGbQuRbxrVl--