From mboxrd@z Thu Jan 1 00:00:00 1970 From: Janek Kozicki Subject: mismatch_cnt of 128 and 1408. Date: Mon, 24 Mar 2008 08:36:51 +0100 Message-ID: <20080324083651.444cbab3@absurd> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Sender: linux-raid-owner@vger.kernel.org To: linux-raid@vger.kernel.org List-Id: linux-raid.ids Hello, My backup box with raid5 recently suffered a series of power failures. Now I'm doing some recovery hoping that power surges did not damage HDDs. I have here - md0 a raid1 of 3*1GB=1GB (root partition) and - md1 a raid5 of 3*500GB=1000GB (backup partition) and - md2 a raid1 of 3*4GB=4GB (swap). I did following things: 1. power on the server, and incidentally mount count for md1 enforced an fsck which found two errors. 2. /usr/share/mdadm/checkarray -a which does a resync of all raid partitions. It takes 5 hours for the 1TB backup partition. 3. afterwards the command: cat /sys/block/md?/md/mismatch_cnt gave answer: md0: 128 md1: 0 md2: 1408 4. touch /forcefsck ; shutdown -r now 5. then after reboot: /usr/share/mdadm/checkarray -a ; cat /sys/block/md?/md/mismatch_cnt md0: 128 md1: 0 md2: 1408 Now I am alarmed that something might be wrong with the root partition. From other posts I remember that mismatch count for swap partitions is allowed to be nonzero. I checked smart health status of HDDs with smartctl -H and the drives are healthy. Is mismatch count = 128 an indication of bad HDD? How to discover which one is bad? -- Janek Kozicki |