From owner-freebsd-fs@FreeBSD.ORG Tue Mar 12 09:33:47 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 92174901 for ; Tue, 12 Mar 2013 09:33:47 +0000 (UTC) (envelope-from peter.maloney@brockmann-consult.de) Received: from moutng.kundenserver.de (moutng.kundenserver.de [212.227.17.10]) by mx1.freebsd.org (Postfix) with ESMTP id 13D4A677 for ; Tue, 12 Mar 2013 09:33:47 +0000 (UTC) Received: from [10.3.0.26] ([141.4.215.32]) by mrelayeu.kundenserver.de (node=mreu4) with ESMTP (Nemesis) id 0M2CHo-1V4pkU08m4-00s8Es; Tue, 12 Mar 2013 10:33:46 +0100 Message-ID: <513EF679.2080402@brockmann-consult.de> Date: Tue, 12 Mar 2013 10:33:45 +0100 From: Peter Maloney User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/17.0 Thunderbird/17.0 MIME-Version: 1.0 To: Cody Ritts Subject: Re: Aligning MBR for ZFS boot help References: <513C1629.50501@caltel.com> In-Reply-To: <513C1629.50501@caltel.com> X-Enigmail-Version: 1.5 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Provags-ID: V02:K0:kmknN+RWGhdQeaB54jmzQVrRkNXnDp2QGvsdMJSOmxZ 8jysFi1+xfsUx1Qmm2trYvsI9jnIjEny0Bd1z5RPXB5mfNS75J vGOqJ7jmvy71ypPR6Cp8Cjx1ucLYrG24uGX9WNv4WWxAJcrXU3 KI8bx6E2Pd+nFsdefHRdLSwt+PLi7aYDWKIjSV2I32kFjVWWu3 l41lWySaPKEt4jSYuAnrz7WNTxDz5xb8SqFKMP2H7rhfn9Wshe fTbv1ce5nWkGppmoU5JLqQwuODdAw6haly5nj54irQNr7hUv/E zNK7lrndHYu3pUltGz3R7vAbIPyn+GfkJ37E+aTpEEkX1LPza3 YipuMvgCLGj8ESTF7fJnwCxs1DiKqST5U3VED5Vo7 Cc: freebsd-fs@freebsd.org 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: Tue, 12 Mar 2013 09:33:47 -0000 On 2013-03-10 06:12, Cody Ritts wrote: > I think remember reading that freebsd-zfs had to be the first slice (I > cannot remember where i read that). And it apparently does not think > an offset is funny. For the gptzfsboot boot loader (and don't know which others), the bootable zfs slice has to be in the same pool as the first slice found. Or in other words, the first ZFS slice found by the bootloader must be the cache, log, or data vdev of the bootable pool. I learned this the hard way ;) www.freebsd.org/cgi/query-pr.cgi?pr=160706 eg. this would fail: slice 1 - freebsd-boot slice 2 - zfs /tank slice 3 - zfs root with /boot this would also fail: slice 1 - freebsd-boot slice 2 - zfs /tank L2ARC cache slice 3 - zfs root with /boot this would probably work (fits the rule, but I didn't test it): slice 1 - freebsd-boot slice 2 - zfs root L2ARC cache slice 3 - zfs /tank slice 4 - zfs root with /boot and this will definitely work: slice 1 - freebsd-boot slice 2 - zfs root with /boot slice 3 - zfs /tank Above examples are with gptzfsboot loader; not sure if you need a freebsd-boot for others. And FYI in possibly all BIOS machines (non-EFI), the boot slice probably needs to be before a certain sector... not sure which number, maybe 2.2TB/2.0TiB. I always just put it first. On my FreeBSD zfs machines, I put it at sector 34 which is badly aligned but means the next regular one can start at 2048, which saves me a whole megabyte! -- -------------------------------------------- Peter Maloney Brockmann Consult Max-Planck-Str. 2 21502 Geesthacht Germany Tel: +49 4152 889 300 Fax: +49 4152 889 333 E-mail: peter.maloney@brockmann-consult.de Internet: http://www.brockmann-consult.de --------------------------------------------