From owner-freebsd-questions@freebsd.org Fri Jul 3 02:08:24 2015 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 AA29E993861 for ; Fri, 3 Jul 2015 02:08:24 +0000 (UTC) (envelope-from quartz@sneakertech.com) Received: from douhisi.pair.com (douhisi.pair.com [209.68.5.179]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 8CEE9114A for ; Fri, 3 Jul 2015 02:08:24 +0000 (UTC) (envelope-from quartz@sneakertech.com) Received: from [10.2.2.1] (pool-173-48-121-235.bstnma.fios.verizon.net [173.48.121.235]) by douhisi.pair.com (Postfix) with ESMTPSA id 139063F745 for ; Thu, 2 Jul 2015 22:08:17 -0400 (EDT) Message-ID: <5595EE90.5050105@sneakertech.com> Date: Thu, 02 Jul 2015 22:08:16 -0400 From: Quartz User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:10.0.2) Gecko/20120216 Thunderbird/10.0.2 MIME-Version: 1.0 To: FreeBSD questions Subject: slightly off topic: SMART error values for seagate drives Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 03 Jul 2015 02:08:24 -0000 Is anyone familiar with exactly how the raw_read_error_rate, reallocated_sector_count, seek_error_rate, hardware_crc_recovered, and udma_crc_error_count values work for seagate drives? AFAIK at least some of these fields list the (average?) number of sectors between errors, and thus a higher raw value is better ...I think. I have several apparently healthy seagate drives with very high rrer/ser/her raw values that seem to support this. I recently took an older disk out of storage, and as part of my system building procedure I always run a few tests over it before putting it back into service. Initially it also had high rrer/ser/her raw values. It failed a SMART extended test at about 40% remaining with a read failure, and the udma_crc_error_count jumped from 0 to 5. I know sometimes this can be just transient flakiness, so I just zeroed out the entire drive with dd to exercise all the sectors and force any remappings. Now, the reallocated_sector_count bumped up to 9, and the raw_read_error_rate and hardware_crc_recovered fields plummeted from the millions down to like 13 ...and have since slowly risen to the 40's. I can't tell what's going on with SMART values anymore, every vendor does things differently and nothing's ever documented. Is having the reallocated sectors value go up still a bad thing, or did seagate change what this means? Why did the read error rate and crc recovered fields bottom out, but the seek error rate is still in the clouds? Is this drive failing, or fine, or what?