From owner-freebsd-questions@freebsd.org Wed Oct 19 23:54:16 2016 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id A07DEC198AE for ; Wed, 19 Oct 2016 23:54:16 +0000 (UTC) (envelope-from citrin@citrin.ru) Received: from hz.citrin.ru (hz.citrin.ru [88.198.212.3]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 662D2AF8 for ; Wed, 19 Oct 2016 23:54:15 +0000 (UTC) (envelope-from citrin@citrin.ru) Received: from x220.lan (c-24-60-168-172.hsd1.ct.comcast.net [24.60.168.172]) by hz.citrin.ru (Postfix) with ESMTPSA id BB4902887B9 for ; Wed, 19 Oct 2016 23:54:07 +0000 (UTC) Subject: Re: Drive Read Errors To: freebsd-questions@freebsd.org References: <7353bec4-4a98-7e86-bda9-4c401bb2ad71@fastmail.com> From: Anton Yuzhaninov Message-ID: <0916225e-d618-d08a-df98-778e9ed23642@citrin.ru> Date: Wed, 19 Oct 2016 19:54:05 -0400 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:45.0) Gecko/20100101 Thunderbird/45.4.0 MIME-Version: 1.0 In-Reply-To: <7353bec4-4a98-7e86-bda9-4c401bb2ad71@fastmail.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=citrin.ru; s=s0; t=1476921248; bh=kSIKBtIFseC34ZIMR4gq8h8gVgjsrqWcDjlAXi4WcD4=; h=Subject:To:References:From:Message-ID:Date:MIME-Version:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=XNNGVvNrxPWj/tdN88/+H22r+pHOW0v06j640sonJEW/0vxemgWjTebKjoKSCR3EDhfARiRlmYw5zLvf1GRX8jxtT4vFFwOZl826CLwqVIPNwJRB3XHuyIMfVvv/qHzAycnn1IWKRAoS9nmPGqnJE1fXOTVu/2vj52241SS+Zik= X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 19 Oct 2016 23:54:16 -0000 On 10/17/16 13:02, Jason C. Wells wrote: > I recently used smartmontools long test and discovered that the drive > had read errors. > > In your experience, is there any value in trying to use drive by mapping > bad sectors or partitioning around the errors? 1. There is a value if your plan to use this HDD for not important data and downtime is also tolerable. 2. FYI: Remapping of bad sectors nowadays is done by disk's firmware. To make it happen just write any data to a all bad sectors. If disk is clean just run: dd if=/dev/zero of=/dev/adaX bs=256k then rerun SMART slef-test (and or dd if=/dev/adaX of=/dev/null). 3. Many people suggest to throw drive with bad sectors away. Such disk will likely have new pending sectors in future and probability of complete fail is higher than for drive with good SMART, but they can work for years after bad sectors are remapped. All depends on requirements for reliability and budget your have. At home I've used HDD which had slef-test fail and Current_Pending_Sector > 0 in past (for temporary data). See also: https://www.backblaze.com/blog/what-smart-stats-indicate-hard-drive-failures/