From owner-freebsd-geom@FreeBSD.ORG Wed May 4 23:00:51 2011 Return-Path: Delivered-To: freebsd-geom@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 57B721065670 for ; Wed, 4 May 2011 23:00:51 +0000 (UTC) (envelope-from aragon@phat.za.net) Received: from mail.geek.sh (decoder.geek.sh [196.36.198.81]) by mx1.freebsd.org (Postfix) with ESMTP id E52168FC15 for ; Wed, 4 May 2011 23:00:50 +0000 (UTC) Received: from igor.geek.sh (196-209-90-218.dynamic.isadsl.co.za [196.209.90.218]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by mail.geek.sh (Postfix) with ESMTPSA id 2172F3B2F5 for ; Thu, 5 May 2011 00:41:50 +0200 (SAST) Message-ID: <4DC1D62C.5070705@phat.za.net> Date: Thu, 05 May 2011 00:41:48 +0200 From: Aragon Gouveia User-Agent: Mozilla/5.0 (X11; U; FreeBSD amd64; en-US; rv:1.9.2.15) Gecko/20110404 Thunderbird/3.1.9 MIME-Version: 1.0 To: freebsd-geom@freebsd.org Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: partitioning dilemma X-BeenThere: freebsd-geom@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: GEOM-specific discussions and implementations List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 04 May 2011 23:00:51 -0000 Hi, Between MBR and GPT, I'm struggling to find the right partitioning scheme to meet my requirements. Suggestions on below would be highly appreciated. I have 2 disks. I want 2 independent gmirror volumes, ie. 2 partitions on each disk, with one partition from each disk in a gmirror volume. Each gmirror volume would contain a bootable FreeBSD system (BSD label), and I'd selectively boot between them when testing new releases or other big changes. Then I'd like a 3rd partition on each disk, both of which for swap space. Then a 4th partition on each disk which I plan to use as a ZFS mirrored ZIL. Finally, a 5th partition on each disk which would both serve as ZFS L2ARC. My dilemma: All documentation and mailing list discussion about GPT seems to indicate that creating BSD labels inside GPT partitions is a Bad Idea, which would mean putting two GPT partitions into a gmirror volume is a bad idea. Is this still the case? My attempts at using MBR and EBR instead of GPT are discouraging once I get to the point of creating an EBR. From what I can gather, default kernel build options specify "options GEOM_PART_EBR_COMPAT" which prevents GEOM from editing EBR partition schemes: # gpart show ada3s4 => 0 267068592 ada3s4 EBR (127G) 0 267068592 - free - (127G) # gpart add -s 67221504 -t freebsd ada3s4 gpart: pre-check failed: Operation canceled Ok, so I guess I can recompile without that kernel option, but I'm sure there's a good reason it's a default option... Is EBR also considered a Bad Idea? Any suggestions? Thanks, Aragon