From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lists.gentoo.org (pigeon.gentoo.org [208.92.234.80]) by finch.gentoo.org (Postfix) with ESMTP id D83071381F3 for ; Mon, 16 Sep 2013 06:50:09 +0000 (UTC) Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 37238E0AFF; Mon, 16 Sep 2013 06:49:59 +0000 (UTC) Received: from mail-qc0-f174.google.com (mail-qc0-f174.google.com [209.85.216.174]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (No client certificate requested) by pigeon.gentoo.org (Postfix) with ESMTPS id 0D423E0AF6 for ; Mon, 16 Sep 2013 06:49:57 +0000 (UTC) Received: by mail-qc0-f174.google.com with SMTP id n9so2394569qcw.5 for ; Sun, 15 Sep 2013 23:49:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=cBA96u9pFOgv1WDKUI5PxCSFCKq2b75/MaUdAwSVd74=; b=Ns4WT6f0tL2ptPD3lppfoHk71v7HrJkry4WujPjiWcrM9YO8LjS+a1w0OuaaUfdmDI ADI37anI9gYoQOp8k17hKEwS+oj8BbfixjnQNn4vmPAu6zKNA1qWB4OtXhpD16sOtlEy cNmXtiKwhLDfrdGsgixOoAmTkI6KwoiJpTNdPSwRbV5QNuImasPE7UvDQSxr1aYKLi/1 w6Scm6h6iHDOwhLJyHb3vhDN9vuDoISne3WUloz/Lat1bAzk869kX5Pk2bdACvj0quo2 s8RvTg01bNP6WdQG+a1iQvyQJ4A8nK8NJmaDpNXjy4W77iW42NQ6934z8KidjNQVrPHU tppQ== Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-user@lists.gentoo.org Reply-to: gentoo-user@lists.gentoo.org MIME-Version: 1.0 X-Received: by 10.229.185.68 with SMTP id cn4mr44143495qcb.5.1379314197164; Sun, 15 Sep 2013 23:49:57 -0700 (PDT) Received: by 10.140.25.83 with HTTP; Sun, 15 Sep 2013 23:49:57 -0700 (PDT) In-Reply-To: <523474C4.7080007@orlitzky.com> References: <5233792D.7040900@orlitzky.com> <3910524.4C314ckqDu@wstn> <52339798.5000409@gmail.com> <523474C4.7080007@orlitzky.com> Date: Sun, 15 Sep 2013 23:49:57 -0700 Message-ID: Subject: Re: [gentoo-user] {OT} Need a new server From: Grant To: Gentoo mailing list Content-Type: text/plain; charset=ISO-8859-1 X-Archives-Salt: 53b12355-851c-4435-8d16-3179ba715e62 X-Archives-Hash: 950a335ebecb01fd5ba4b6cbd336a365 >> Instead, how about a 6-drive RAID 10 array with no hot spare? My >> guess is this would mean much greater fault-tolerance both overall and >> during the rebuild process (once a new drive is swapped in). That >> would mean not only potentially increased uptime but decreased >> monitoring responsibility. > > RAID10 with six drives can be implemented one of two ways, > > Type 1: A B A B A B > > Type 2: A B C A B C > > If your controller can do Type 1, then going with six drives gives you > better fault tolerance than four with a hot spare. > > I've only ever seen Type 2, so I would bet that's what your controller > will do. It's easy to check: set up RAID10 with four drives, then with > six. Did the drive get bigger? If so, it's Type 2. > > If it's Type 2, then four drives with a spare is equally tolerant. > Slightly better, even, if you take into account the reduced probability > of 2/5 of the drives failing compared to 2/6. Thank you very much for this info. I had no idea. Is there another label for these RAID types besides "Type 1" and "Type 2"? I can't find reference to those designations via Google. - Grant