From owner-freebsd-fs@FreeBSD.ORG Wed Jul 11 01:51:59 2012 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 98DD31065680 for ; Wed, 11 Jul 2012 01:51:59 +0000 (UTC) (envelope-from rincebrain@gmail.com) Received: from mail-pb0-f54.google.com (mail-pb0-f54.google.com [209.85.160.54]) by mx1.freebsd.org (Postfix) with ESMTP id 6B3658FC0C for ; Wed, 11 Jul 2012 01:51:59 +0000 (UTC) Received: by pbbro2 with SMTP id ro2so1343300pbb.13 for ; Tue, 10 Jul 2012 18:51:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type; bh=lqhDrKe8FtPbPHUjW+ajtB+c2EJQAw23zYm6IJZG2eY=; b=CnNw+l9Y6U5RUBNJ1pUAJvVHgPmVe35pK0859p5MGBIgpCwpc3GgeciwP04KZSa+JD ktwVvD9RuoC0HGS4k1lsPGXONJhIK12EvHgn/dEdMaj4d2xVkJ2W7s5g6Nr1q1Lqm5Vp OX425U5HKP3M2A+5tP6sIJEltgINaJSKrBdinJh7Gh9+WVD8H4Z1mk8Rv/+8byPyGJ6B QO81EU01ed+AJvyH2Gh/8nVyLldyBThtZ2yfZsdv5TpeuKIWO+07LnNt6BIuQYjNPdKl RMNkvdyy0/tZtoOOsl4+Y/9/Z4ElWm4VYIWY6wIVAgVVTQl7MqDieH6b3jZZVdFZi5/l BzVA== MIME-Version: 1.0 Received: by 10.68.201.7 with SMTP id jw7mr19508197pbc.60.1341971519213; Tue, 10 Jul 2012 18:51:59 -0700 (PDT) Sender: rincebrain@gmail.com Received: by 10.68.38.10 with HTTP; Tue, 10 Jul 2012 18:51:59 -0700 (PDT) In-Reply-To: References: <1341946657.18535.YahooMailClassic@web122505.mail.ne1.yahoo.com> Date: Tue, 10 Jul 2012 21:51:59 -0400 X-Google-Sender-Auth: 2R6Y52RMBN4xCTBmofn5Qt2X30g Message-ID: From: Rich To: Bob Friesenhahn Content-Type: text/plain; charset=UTF-8 Cc: Jason Usher , freebsd-fs@freebsd.org Subject: Re: chaining JBOD chassic to server ... why am I scared ? (ZFS) 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: Wed, 11 Jul 2012 01:51:59 -0000 *waves with his 360 disks attached to single head node* c.f. http://www.senecadata.com/products/vendor-partners/LSI/PDFs/Seneca-PSC-LSI.pdf (which is not me, but is relevant) - Rich On Tue, Jul 10, 2012 at 9:19 PM, Bob Friesenhahn wrote: > On Tue, 10 Jul 2012, Jason Usher wrote: >> >> >> But this scares me ... >> >> - two different power sources - so the "head unit" can lose power >> independent of the JBOD device ... how well does that turn out ? > > > Most of your concerns are things which have been normal for fiber channel > based arrays for quite a few years already. SAS cables are shorter so there > is a better chance that everything is on the same power and in the same > rack. > >> From my limited experience, getting everything on the same power helps > > with managing things. > > >> Just how well does ZFS v28 deal with these kind of situations, and do I >> have a good reason to be awfully shy about doing this ? > > > I have been on zfs mailing lists for many years and few of the issues > reported have been due to ZFS. Usually problems are due to failing memory, > bad cables, and SATA drives on SAS expanders. SAS disks work better in > large arrays. > > There have been people running several hundred disks without problem. > > Bob > -- > Bob Friesenhahn > bfriesen@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/ > GraphicsMagick Maintainer, http://www.GraphicsMagick.org/ > > _______________________________________________ > freebsd-fs@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-fs > To unsubscribe, send any mail to "freebsd-fs-unsubscribe@freebsd.org"