From owner-freebsd-fs@FreeBSD.ORG Mon Jan 7 17:17:05 2008 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 20ED316A421 for ; Mon, 7 Jan 2008 17:17:05 +0000 (UTC) (envelope-from tzhuan@gmail.com) Received: from fg-out-1718.google.com (fg-out-1718.google.com [72.14.220.155]) by mx1.freebsd.org (Postfix) with ESMTP id 9901E13C4F0 for ; Mon, 7 Jan 2008 17:17:04 +0000 (UTC) (envelope-from tzhuan@gmail.com) Received: by fg-out-1718.google.com with SMTP id 16so5092776fgg.35 for ; Mon, 07 Jan 2008 09:17:03 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; bh=UiFtb6+cU0UdSnDSQqa7Ohunxpr8LC5yIQE2rDxW+O0=; b=iJlyTltjHMiCYl/bvpzM5zx+Hxmk2mBJfZlMKs3SpJXzZq5sPJAZ3mW8vfgD0p+9rKRK5G3d3AG+1Pb2f6hqJ4PgxzG4QwCcWqW4GTC0plplKC33UcZceXzYFK1HzalJmqLV+UADtHC4X/jMmFpY5hS9KNyAlK28HRBO0LEsqls= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:sender:to:subject:cc:in-reply-to:mime-version:content-type:content-transfer-encoding:content-disposition:references:x-google-sender-auth; b=tpF62mr2NnyI3EO89qFMltWw08ylfGd3ezjoQGPNtjv2bBfP0lhV/B4S9y0LEjzpOkxABY9kq9kE3nvNd74yrYRBa5WF6rdXGXtx9rK+6AMvOWpQVne8vZsIYFwQ9Sn5k4Qf3M4mYgbsVh22lu0PDosCq0oAY2FPzTLzb9VAhgc= Received: by 10.86.66.1 with SMTP id o1mr20313303fga.36.1199726223597; Mon, 07 Jan 2008 09:17:03 -0800 (PST) Received: by 10.86.23.20 with HTTP; Mon, 7 Jan 2008 09:17:03 -0800 (PST) Message-ID: <6a7033710801070917w4b453f10l7115bd9fe3a53a1b@mail.gmail.com> Date: Tue, 8 Jan 2008 01:17:03 +0800 From: "Tz-Huan Huang" Sender: tzhuan@gmail.com To: ticso@cicely.de In-Reply-To: <20080107135925.GF65134@cicely12.cicely.de> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <477B16BB.8070104@freebsd.org> <20080102070146.GH49874@cicely12.cicely.de> <477B8440.1020501@freebsd.org> <200801031750.31035.peter.schuller@infidyne.com> <477D16EE.6070804@freebsd.org> <20080103171825.GA28361@lor.one-eyed-alien.net> <6a7033710801061844m59f8c62dvdd3eea80f6c239c1@mail.gmail.com> <20080107135925.GF65134@cicely12.cicely.de> X-Google-Sender-Auth: e5fa2e18a4fdf515 Cc: freebsd-fs@freebsd.org, Brooks Davis Subject: Re: ZFS i/o errors - which disk is the problem? 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: Mon, 07 Jan 2008 17:17:05 -0000 2008/1/7, Bernd Walter : > The data is corrupted by controller and/or disk subsystem. > You have no other data sources for the broken data, so it is lost. > The only garantied way is to get it back from backup. > Maybe older snapshots/clones are still readable - I don't know. > Nevertheless data is corrupted and that's the purpose for alternative > data sources such as raidz/mirror and at last backup. > You shouldn't have ignored those errors at first, because you are > running with faulty hardware. > Without ZFS checksumming the system would just process the broken > data with unpredictable results. > If all those errors are fresh then you likely used a broken RAID > controller below ZFS, which silently corrupted syncronity and then > blow when disk state changed. > Unfortunately many RAID controllers are broken and therefor useless. Hi, Thank you very much for your answer. We have run the self-test for all raid controllers and they all reported ok. Do you mean that many raid controllers are broken (buggy?) even if the self-test is passed? If all the disks are pass-through to the zfs, is it the safe way to use the buggy controllers? Thank you very much. Sincerely yours, Tz-Huan