From owner-freebsd-fs@FreeBSD.ORG Wed Nov 14 02:30:22 2012 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id EE894433; Wed, 14 Nov 2012 02:30:22 +0000 (UTC) (envelope-from bfriesen@simple.dallas.tx.us) Received: from blade.simplesystems.org (blade.simplesystems.org [65.66.246.74]) by mx1.freebsd.org (Postfix) with ESMTP id A902D8FC08; Wed, 14 Nov 2012 02:30:22 +0000 (UTC) Received: from freddy.simplesystems.org (freddy.simplesystems.org [65.66.246.65]) by blade.simplesystems.org (8.14.4+Sun/8.14.4) with ESMTP id qAE2UCGM021771; Tue, 13 Nov 2012 20:30:12 -0600 (CST) Date: Tue, 13 Nov 2012 20:30:12 -0600 (CST) From: Bob Friesenhahn X-X-Sender: bfriesen@freddy.simplesystems.org To: Julian Elischer Subject: Re: RHEL to FreeBSD file server In-Reply-To: <50A2F804.3010009@freebsd.org> Message-ID: References: <50A130B7.4080604@cse.yorku.ca> <20121113043409.GA70601@neutralgood.org> <50A2B95D.4000400@cse.yorku.ca> <50A2F804.3010009@freebsd.org> User-Agent: Alpine 2.01 (GSO 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.2 (blade.simplesystems.org [65.66.246.90]); Tue, 13 Nov 2012 20:30:12 -0600 (CST) 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: Wed, 14 Nov 2012 02:30:23 -0000 On Tue, 13 Nov 2012, Julian Elischer wrote: > On 11/13/12 1:19 PM, Jason Keltz wrote: >> On 11/13/2012 12:41 PM, Bob Friesenhahn wrote: >>> On Mon, 12 Nov 2012, kpneal@pobox.com wrote: >> >> Initially, I had one storage chassis, split between 2 LSI 9205-8e >> controllers with a 22 disk pool comprised of 11 mirrored vdevs. >> I think that I'm still slightly uncomfortable with the fact that 2 disks, >> which were all purchased at the same time, could essentially die at the >> same time, killing my whole pool. Yet, while moving to raidz2 would allow >> better redundancy, I'm not sure if the raidz2 rebuild time and decrease in >> performance would be worth it.. The concern about a bad batch of disks is a valid concern. Of course a bad batch of disks could even bring down raidz2. If this is a concern, then purchase the disks from two different vendors. >> I'll buy another md1220, a few more disks, add another 9205-8e card... and >> use triple mirrored vdevs instead of dual.... I only really need about 8 x Triple mirror is considered to be exceedingly reliable. Not very cost effective though. Reads will be faster than with simple mirror since any one of the three disks can satisfy a read request. Bob -- Bob Friesenhahn bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer, http://www.GraphicsMagick.org/