From owner-freebsd-questions@FreeBSD.ORG Tue Aug 26 07:17:51 2014 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 5E4484D5 for ; Tue, 26 Aug 2014 07:17:51 +0000 (UTC) Received: from sdf.lonestar.org (mx.sdf.org [192.94.73.24]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "mx.sdf.org", Issuer "SDF.ORG" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 3B38F31C4 for ; Tue, 26 Aug 2014 07:17:50 +0000 (UTC) Received: from sdf.org (IDENT:bennett@sdf.lonestar.org [192.94.73.15]) by sdf.lonestar.org (8.14.8/8.14.5) with ESMTP id s7Q7Hksv006220 (using TLSv1/SSLv3 with cipher DHE-RSA-AES256-GCM-SHA384 (256 bits) verified NO); Tue, 26 Aug 2014 07:17:46 GMT Received: (from bennett@localhost) by sdf.org (8.14.8/8.12.8/Submit) id s7Q7Hkua012200; Tue, 26 Aug 2014 02:17:46 -0500 (CDT) From: Scott Bennett Message-Id: <201408260717.s7Q7Hkua012200@sdf.org> Date: Tue, 26 Aug 2014 02:17:46 -0500 To: kpneal@pobox.com Subject: Re: some ZFS questions References: <201408070816.s778G9ug015988@sdf.org> <40AF5B49-80AF-4FE2-BA14-BFF86164EAA8@kraus-haus.org> <201408211007.s7LA7YGd002430@sdf.org> <201408241015.s7OAFRv7010196@sdf.org> <20140825014249.GA28995@neutralgood.org> In-Reply-To: <20140825014249.GA28995@neutralgood.org> User-Agent: Heirloom mailx 12.4 7/29/08 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: freebsd-questions@freebsd.org X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 26 Aug 2014 07:17:51 -0000 kpneal@pobox.com wrote: > On Sun, Aug 24, 2014 at 05:15:27AM -0500, Scott Bennett wrote: > > Paul Kraus wrote: > > > ZFS uses the header written to the device to identify it. Note that this was not always the case and *if* you have a zfs cache file you *may* run into device renaming issues. I have not seen any, but I am also particularly paranoid about not moving devices around before exporting them. I have seen too many stories of lost zpools due to this many years ago on the ZFS list. > > > > Well, I don't have an SSD at present, so maybe it won't matter then. > > Nevertheless, if a crash and reboot can result in loss of a pool because > > the device names get reshuffled, that would seem like a real hazard to > > using ZFS, so I hope that is no longer the case. > > If you can use GPT partitioning then you can have GPT labels on partitions > spanning entire disks. Then you can rearrange physical disks to your hearts > content. Of course, doing it that way, as opposed to giving ZFS the raw devices, is what others here have been recommending against for compatibility reasons. > > The bonus is that you can put identifying information in the label name > to be even more sure you are replacing the correct disk when the time > comes. > Certainly. Scott Bennett, Comm. ASMELG, CFIAG ********************************************************************** * Internet: bennett at sdf.org *xor* bennett at freeshell.org * *--------------------------------------------------------------------* * "A well regulated and disciplined militia, is at all times a good * * objection to the introduction of that bane of all free governments * * -- a standing army." * * -- Gov. John Hancock, New York Journal, 28 January 1790 * **********************************************************************