From owner-freebsd-stable@FreeBSD.ORG Sun Apr 17 18:49:15 2011 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 28F85106564A for ; Sun, 17 Apr 2011 18:49:15 +0000 (UTC) (envelope-from jdc@koitsu.dyndns.org) Received: from qmta02.westchester.pa.mail.comcast.net (qmta02.westchester.pa.mail.comcast.net [76.96.62.24]) by mx1.freebsd.org (Postfix) with ESMTP id C804F8FC14 for ; Sun, 17 Apr 2011 18:49:14 +0000 (UTC) Received: from omta06.westchester.pa.mail.comcast.net ([76.96.62.51]) by qmta02.westchester.pa.mail.comcast.net with comcast id YioX1g00316LCl052ipEdj; Sun, 17 Apr 2011 18:49:14 +0000 Received: from koitsu.dyndns.org ([67.180.84.87]) by omta06.westchester.pa.mail.comcast.net with comcast id YipD1g00K1t3BNj3SipEwF; Sun, 17 Apr 2011 18:49:14 +0000 Received: by icarus.home.lan (Postfix, from userid 1000) id 4FEDF9B42B; Sun, 17 Apr 2011 11:49:12 -0700 (PDT) Date: Sun, 17 Apr 2011 11:49:12 -0700 From: Jeremy Chadwick To: Lystopad Olexandr Message-ID: <20110417184912.GA55678@icarus.home.lan> References: <20110417123232.GA96423@laa.zp.ua> <20110417161440.GB96423@laa.zp.ua> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110417161440.GB96423@laa.zp.ua> User-Agent: Mutt/1.5.21 (2010-09-15) Cc: freebsd-stable@freebsd.org, George Kontostanos Subject: Re: ZFS root on MB Intel S3420GP 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: Sun, 17 Apr 2011 18:49:15 -0000 On Sun, Apr 17, 2011 at 08:14:40PM +0400, Lystopad Olexandr wrote: > On Sun, Apr 17, 2011 at 04:54:34PM +0300 > gkontos.mail@gmail.com wrote about "Re: ZFS root on MB Intel S3420GP": > > There is a nice guide in the WIKI regarding how to install your system with > > ZFS on root. > > > > http://wiki.freebsd.org/RootOnZFS/GPTZFSBoot/RAIDZ2 > > > > In any case don't configure the raid in your controller and let ZFS take > > care of this. > > Thanks for answer! > > Is it possible to hot change disks with zfs raid on my motherboard? This has little to do with ZFS and more to do with SATA. You will need a hot-swap backplane for this to be possible. Decent server chassis usually provide this. We use Supermicro systems with hot-swap backplanes and they work fantastic with FreeBSD + ahci.ko. If you do not have a hot-swap backplane, there is a very good chance "strange things" will happen when you yank power or the signal cable. I've personally tried it on a test system without a hot-swap bay. When I pulled the SATA power connector from the hard disk, I saw a blue spark near the power connector and the entire system lost power. I've blogged about hot-swapping SATA disks on FreeBSD with ZFS in use and with ahci.ko, with full kernel output and all necessary details: http://koitsu.wordpress.com/2010/07/22/freebsd-and-zfs-hot-swapping-sata-disks-with-ahci/ Please note the blog post demonstrated how I went about upgrading disks without needing to power the system off. Readers have commented how I could have done it all by using the spare bay I had, but I explicitly chose *not* to use that bay for the benefit of the readers who might not have a spare bay. Furthermore, the "zpool offline" steps probably aren't needed (ZFS should note the disk as UNAVAIL immediately and the array should become degraded), same with "zpool online". I should really refine those procedures, or re-do the post for present-day 8.2-RELEASE. When doing administrative/maintenance tasks, I tend to do as much possible to ensure the kernel/system knows what I'm about to do. :-) If you want me to perform an actual disk failure (literally yanking a disk out of a bay while the disk is in use + part of a ZFS pool), I can do that without any worry and provide the results here. Just ask. -- | Jeremy Chadwick jdc@parodius.com | | Parodius Networking http://www.parodius.com/ | | UNIX Systems Administrator Mountain View, CA, USA | | Making life hard for others since 1977. PGP 4BD6C0CB |