From owner-freebsd-database Fri Apr 12 10:13:58 2002 Delivered-To: freebsd-database@freebsd.org Received: from mail.wolves.k12.mo.us (mail.wolves.k12.mo.us [207.160.214.1]) by hub.freebsd.org (Postfix) with ESMTP id F38A337B42A for ; Fri, 12 Apr 2002 10:13:50 -0700 (PDT) Received: from mail.wolves.k12.mo.us (cdillon@mail.wolves.k12.mo.us [207.160.214.1]) by mail.wolves.k12.mo.us (8.9.3/8.9.3) with ESMTP id MAA51374; Fri, 12 Apr 2002 12:13:27 -0500 (CDT) (envelope-from cdillon@wolves.k12.mo.us) Date: Fri, 12 Apr 2002 12:13:26 -0500 (CDT) From: Chris Dillon To: David Drum Cc: FreeBSD DB List Subject: Re: Raid configuration In-Reply-To: <20020411235022.GA21045@elvis.mu.org> Message-ID: <20020412120947.Q48494-100000@mail.wolves.k12.mo.us> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-database@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Thu, 11 Apr 2002, David Drum wrote: > Quoth Jim C. Nasby: > > > FWIW, RAID10 is not two seperate mirrors, it's a single volume. It's > > either a mirror of two striped volumes (yuck), or a stripe of mirrored > > volumes. > > The first description you give is RAID 0+1, the second is RAID 1+0. > There is a difference. If a disk goes bad in a RAID 0+1, you've lost an > entire mirror, because the whole stripe is gone. If a disk goes bad in > a RAID 1+0, you've only lost one mirrored drive, and not a whole stripe. And when you only have a four-drive configuration, it makes no difference which one you use since the chances of a total failure is exactly the same either way. Any more drives than that and you definately want RAID10. :-) -- Chris Dillon - cdillon@wolves.k12.mo.us - cdillon@inter-linc.net FreeBSD: The fastest and most stable server OS on the planet - Available for IA32 (Intel x86) and Alpha architectures - IA64, PowerPC, UltraSPARC, and ARM architectures under development - http://www.freebsd.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-database" in the body of the message