From owner-freebsd-questions@FreeBSD.ORG Fri Jun 1 14:30:37 2012 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id B168A1065679 for ; Fri, 1 Jun 2012 14:30:37 +0000 (UTC) (envelope-from feenberg@nber.org) Received: from mail2.nber.org (mail2.nber.org [66.251.72.79]) by mx1.freebsd.org (Postfix) with ESMTP id 607DB8FC36 for ; Fri, 1 Jun 2012 14:30:36 +0000 (UTC) Received: from sas1.nber.org (sas1.nber.org [66.251.72.185]) by mail2.nber.org (8.14.4/8.14.4) with ESMTP id q51E73Gv059893 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Fri, 1 Jun 2012 10:07:04 -0400 (EDT) (envelope-from feenberg@nber.org) Date: Fri, 1 Jun 2012 10:07:03 -0400 (EDT) From: Daniel Feenberg To: Wojciech Puchar In-Reply-To: Message-ID: References: User-Agent: Alpine 2.00 (DEB 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Anti-Virus: Kaspersky Anti-Virus for Linux Mail Server 5.6.39/RELEASE, bases: 20120601 #8116517, check: 20120601 clean Cc: Kaya Saman , freebsd-questions@freebsd.org, Oscar Hodgson Subject: Re: Anyone using freebsd ZFS for large storage servers? 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: Fri, 01 Jun 2012 14:30:37 -0000 On Fri, 1 Jun 2012, Wojciech Puchar wrote: >>> Assuming that filesystem doesn't need offline filesystem check utility >>> because it "never crash" is funny. >>> >> >> zfs scrub...??? > > when starting means crash quickly? > Well.. no. > > Certainly with computers that never have hardware faults and assuming ZFS > doesn't have any software bugs you may be right. > > But in real world you will be hardly punished some day ;) > >> Additionally ZFS works directly at the block level of the HD meaning >> that it is slightly different to the 'normal' file systems in storing >> information and is also "self healing"...... > > doesn't other filesystem work on block level too? if no - then at what level? > If the OP really intended to stripe disks with no parity or mirror for ZFS , then that is probably a mistake. If the disks are /tmp, it might make sense to stripe disks without parity, but no need for ZFS. The OP did say "JBOD", which to me means that each disk is a separate disk partition with no striping or parity. Again, in that case I don't see any need for ZFS. As for ZFS being dangerous, we have a score of drive-years with no loss of data. The lack of fsck is considered in this intelligently written piece http://www.osnews.com/story/22423/Should_ZFS_Have_a_fsck_Tool_ The link to the emotional posting by Jeff Bomwick is broken, but the original is available at: http://mail.opensolaris.org/pipermail/zfs-discuss/2008-October/022324.html daniel feenberg nber