From owner-freebsd-questions@FreeBSD.ORG Wed Mar 12 14:37:17 2008 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id BE135106566B for ; Wed, 12 Mar 2008 14:37:17 +0000 (UTC) (envelope-from dan@dan.emsphone.com) Received: from dan.emsphone.com (dan.emsphone.com [199.67.51.101]) by mx1.freebsd.org (Postfix) with ESMTP id 8B4318FC1D for ; Wed, 12 Mar 2008 14:37:17 +0000 (UTC) (envelope-from dan@dan.emsphone.com) Received: (from dan@localhost) by dan.emsphone.com (8.14.2/8.14.2) id m2CEbGg4067904; Wed, 12 Mar 2008 09:37:16 -0500 (CDT) (envelope-from dan) Date: Wed, 12 Mar 2008 09:37:15 -0500 From: Dan Nelson To: kalin m Message-ID: <20080312143714.GB34485@dan.emsphone.com> References: <47D5E08D.1000203@el.net> <283601c88322$b4ba8af0$6900a8c0@tamouh> <47D6D277.40806@el.net> <20080311200804.GA34485@dan.emsphone.com> <47D71617.1070103@el.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <47D71617.1070103@el.net> X-OS: FreeBSD 7.0-PRERELEASE User-Agent: Mutt/1.5.17 (2007-11-01) Cc: "Tamouh H." , freebsd-questions@freebsd.org Subject: Re: RAID X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 12 Mar 2008 14:37:17 -0000 In the last episode (Mar 11), kalin m said: > thanks.... [...] > > in my case the machine showed me the ar0 to install the system on it > without doing this 'quick and dirty way'. > > and now i get: > # atacontrol status ar0 > ar0: ATA RAID1 status: READY > subdisks: > 0 ad4 ONLINE > 1 ad6 ONLINE > > that tells me that i actually do have RAID1 active. which means it's a > software one, correct? Right. The system must have already been set up for RAID when you bought it. > also if you do not mind please elaborate on "MatrixRAID is one of > those not-really-raid controllers that only provides RAID during the > boot process..." All of the controllers handled by the ataraid device are BIOS-only raid controllers. Once the boot process hands control to an operating system, that OS has to manage the RAID itself, making sure that mirrored disks are written to, and rebuilding damaged volumes. This is different from hardware RAID, where external hardware (usually with a battery-backed RAM cache to add performance) manages all of that and the OS just has to read and write blocks to the virtual raid device. -- Dan Nelson dnelson@allantgroup.com