From owner-freebsd-fs@FreeBSD.ORG Sun Nov 29 01:00:16 2009 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 0C20E1065676 for ; Sun, 29 Nov 2009 01:00:16 +0000 (UTC) (envelope-from dimitry@andric.com) Received: from tensor.andric.com (cl-327.ede-01.nl.sixxs.net [IPv6:2001:7b8:2ff:146::2]) by mx1.freebsd.org (Postfix) with ESMTP id C7B3B8FC14 for ; Sun, 29 Nov 2009 01:00:15 +0000 (UTC) Received: from [IPv6:2001:7b8:3a7:0:319f:9c16:d53d:1cec] (unknown [IPv6:2001:7b8:3a7:0:319f:9c16:d53d:1cec]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by tensor.andric.com (Postfix) with ESMTPSA id 25C4E5C43; Sun, 29 Nov 2009 02:00:14 +0100 (CET) Message-ID: <4B11C7A1.1040801@andric.com> Date: Sun, 29 Nov 2009 02:00:17 +0100 From: Dimitry Andric User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.2; en-US; rv:1.9.1.5) Gecko/20091126 Shredder/3.0.1pre MIME-Version: 1.0 To: Wes Morgan References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: freebsd-fs@freebsd.org Subject: Re: raidz configuration X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 29 Nov 2009 01:00:16 -0000 On 2009-11-28 23:22, Wes Morgan wrote: > Simple question: > > 8 devices in a raidz2 > or > 4 devices in a raidz x 2 With the first configuration, any two drives can fail, and all data is still preserved. With the second configuration, if two drives fail within the same RAID set, you are screwed. E.g., if safety is your concern, I would definitely choose the first configuration. :)