From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steven Haigh Subject: Re: Why does one get =?UTF-8?Q?mismatches=3F?= Date: Thu, 21 Jan 2010 15:17:56 +1100 Message-ID: <968ea7bde37a4085f4588f2ef4447d94@localhost> References: <387070.15704.qm@web51305.mail.re2.yahoo.com> <70ed7c3e1001201244k3c734336y8e145bb50f88de26@mail.gmail.com> <70ed7c3e1001201430i72023a9fq1341b671073ac53c@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: Sender: linux-raid-owner@vger.kernel.org To: Brett Russ Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids On Wed, 20 Jan 2010 17:43:45 -0500, Brett Russ wrote: > On 01/20/2010 05:30 PM, Majed B. wrote: >> He needs to run a full offline or long test before checking with >> smartctl -a -- since it won't show any sector errors if those tests >> weren't run at least once. > > Not sure I agree with that. The md checks he's been doing will cause a > read of all data regions of the relevant partition and if the disk is > throwing errors, those sectors should be marked probational. Then, if a > subsequent repair ends up remapping them, those sectors will show up as > remapped. > > The grep will show both probational and remapped sector counts for each > drive. > > BTW, the cmd should also include an echo so it's easy to tell which > drive is being reported: > > for di in a b c d e f g; do echo $di; smartctl -a /dev/sd$di | grep -i > _sect; done Interestingly enough, I'm struggling with a system on this matter too... I can never seem to get rid of mismatches. # for di in a b c d e f g; do echo $di; smartctl -a /dev/hd$di | grep -i sect; done a === START OF INFORMATION SECTION === === START OF READ SMART DATA SECTION === 5 Reallocated_Sector_Ct 0x0033 100 100 036 Pre-fail Always - 0 197 Current_Pending_Sector 0x0012 100 100 000 Old_age Always - 0 b c === START OF INFORMATION SECTION === === START OF READ SMART DATA SECTION === 5 Reallocated_Sector_Ct 0x0033 100 100 036 Pre-fail Always - 0 197 Current_Pending_Sector 0x0012 100 100 000 Old_age Always - 0 Full offline tests of both drives less than 400 power on hours ago all came up clean. No read errors. Just mismatches. I can run a repair on them and STILL have mismatches again after a check. At the moment: # cat /sys/block/md2/md/mismatch_cnt 1024 It's in the middle of a repair now - as quite often the filesystem on /dev/md2 will go read-only due to a journal error. I've tried everything except replacing hardware to figure out what's going on here - but it will do this like clockwork every month. A reboot later and it'll run an fsck, find no errors, then between 21 and 30 days later it will go readonly again. It's annoying as hell and I wish I could get to the bottom of it! -- Steven Haigh Email: netwiz@crc.id.au Web: http://www.crc.id.au Phone: (03) 9001 6090 - 0412 935 897 Fax: (03) 8338 0299