From owner-freebsd-scsi@FreeBSD.ORG Wed May 14 00:56:25 2003 Return-Path: Delivered-To: freebsd-scsi@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6A34737B401; Wed, 14 May 2003 00:56:25 -0700 (PDT) Received: from franky.speednet.com.au (franky.speednet.com.au [203.57.65.5]) by mx1.FreeBSD.org (Postfix) with ESMTP id 2831E43FA3; Wed, 14 May 2003 00:56:24 -0700 (PDT) (envelope-from andyf@speednet.com.au) Received: from hewey.af.speednet.com.au (hewey.af.speednet.com.au [203.38.96.242])h4E7uLYr082526; Wed, 14 May 2003 17:56:22 +1000 (EST) (envelope-from andyf@speednet.com.au) Received: from hewey.af.speednet.com.au (hewey.af.speednet.com.au [172.22.2.17])h4E7uJYm070954; Wed, 14 May 2003 17:56:21 +1000 (EST) (envelope-from andyf@speednet.com.au) Date: Wed, 14 May 2003 17:56:19 +1000 (EST) From: Andy Farkas X-X-Sender: andyf@hewey.af.speednet.com.au To: "Marc G. Fournier" In-Reply-To: <20030513234434.V3557@hub.org> Message-ID: <20030514175000.E69707-100000@hewey.af.speednet.com.au> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII cc: Greg 'groggy' Lehey cc: freebsd-scsi@freebsd.org Subject: Re: RAID5 capacities / usable drive space ... X-BeenThere: freebsd-scsi@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: SCSI subsystem List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 14 May 2003 07:56:25 -0000 On Tue, 13 May 2003, Marc G. Fournier wrote: > On Wed, 14 May 2003, Greg 'groggy' Lehey wrote: > > > Hmm. You know some interesting someones. > > Yup ... > > > Yes, it doesn't make sense to have a RAID-5 volume with less than three > > drives, but in degraded mode it'll run with two. Or it should, bar > > implementation constraints. And theoretically you could hot swap them. > > 'K, I'm going to test the 'theory' out tomorrow just to make double sure > about the 3->2 drive configuration ... since you already know the vinum > internals, I'm more worried about how hardware RAID will handle things ... I had a vinum raid-5 volume lose a disk a few months ago. vinum handled it fine for the couple of weeks while waiting for a replacement (including reboots). Adding in the replacement disk is a whole other story. It may well be worth practicing. Documentation in this area is lacking. -- :{ andyf@speednet.com.au Andy Farkas System Administrator Speednet Communications http://www.speednet.com.au/