From owner-freebsd-stable@FreeBSD.ORG Tue Nov 23 23:04:57 2010 Return-Path: Delivered-To: stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 5E3FF106566B for ; Tue, 23 Nov 2010 23:04:57 +0000 (UTC) (envelope-from peterjeremy@acm.org) Received: from fallbackmx09.syd.optusnet.com.au (fallbackmx09.syd.optusnet.com.au [211.29.132.242]) by mx1.freebsd.org (Postfix) with ESMTP id E18408FC16 for ; Tue, 23 Nov 2010 23:04:56 +0000 (UTC) Received: from mail12.syd.optusnet.com.au (mail12.syd.optusnet.com.au [211.29.132.193]) by fallbackmx09.syd.optusnet.com.au (8.13.1/8.13.1) with ESMTP id oANJWC5P009357 for ; Wed, 24 Nov 2010 06:32:12 +1100 Received: from server.vk2pj.dyndns.org (c220-239-116-103.belrs4.nsw.optusnet.com.au [220.239.116.103]) by mail12.syd.optusnet.com.au (8.13.1/8.13.1) with ESMTP id oANJW8cV013418 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Wed, 24 Nov 2010 06:32:08 +1100 X-Bogosity: Ham, spamicity=0.000000 Received: from server.vk2pj.dyndns.org (localhost.vk2pj.dyndns.org [127.0.0.1]) by server.vk2pj.dyndns.org (8.14.4/8.14.4) with ESMTP id oANJW7Ko010948; Wed, 24 Nov 2010 06:32:07 +1100 (EST) (envelope-from peter@server.vk2pj.dyndns.org) Received: (from peter@localhost) by server.vk2pj.dyndns.org (8.14.4/8.14.4/Submit) id oANJW7Mc010947; Wed, 24 Nov 2010 06:32:07 +1100 (EST) (envelope-from peter) Date: Wed, 24 Nov 2010 06:32:07 +1100 From: Peter Jeremy To: Andrew Reilly Message-ID: <20101123193207.GA10788@server.vk2pj.dyndns.org> References: <20101122113541.GA74719@johnny.reilly.home> <4CEA8BA6.7080009@kc8onw.net> <20101123124543.GA4751@johnny.reilly.home> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="+HP7ph2BbKc20aGI" Content-Disposition: inline In-Reply-To: <20101123124543.GA4751@johnny.reilly.home> X-PGP-Key: http://members.optusnet.com.au/peterjeremy/pubkey.asc User-Agent: Mutt/1.5.20 (2009-06-14) Cc: stable@freebsd.org Subject: Re: ZFS backups: retrieving a few files? 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: Tue, 23 Nov 2010 23:04:57 -0000 --+HP7ph2BbKc20aGI Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On 2010-Nov-23 23:45:43 +1100, Andrew Reilly wrote: >zfs send -vR tank/home@0 | zfs receive -d /backup/snapshots > >in order to experiment with this strategy. > >One would then become alarmed when one discovered that the >receive mechanism also invoked the mountpoint=3D parameter of the >source filesystem, and the zfs propensity for just doing stuff, >and boom: you have a read-only version of your home directory >mounted *on top of* your actual home directory... Been there, done that. The undocumented '-u' option to receive will prevent the receive side performing mounts. The poorly documented '-R' option on import allows you to specify an alternative root mountpoint. Once you have done the initial transfer, you can also set 'canmount=3Dnoauto' on each fileset (it isn't inherited) to prevent ZFS automounting them on import. BTW, the entire export is performed at the current compression level - recompressing existing data. --=20 Peter Jeremy --+HP7ph2BbKc20aGI Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.15 (FreeBSD) iEYEARECAAYFAkzsFrcACgkQ/opHv/APuIfWZACfbG3bUPC39dRq7lRCWgaU4aZV D5kAoMSDKPvd4bvoYtJE68VOQ+lC7gli =NnUI -----END PGP SIGNATURE----- --+HP7ph2BbKc20aGI--