On 01/27/2013 02:26 PM, Wolfgang Denk wrote: > I have seen "mismatch_cnt is not 0" warnings in the past, but that has > always been with RAID 1 arrays, and with relatively small numbers on > /sys/block/md*/md/mismatch_cnt; my understanding was that this was not > actually critical. > > However, after updating to Fedora 18, I get this message from all > updated > systems that have RAID 6 arrays, and with _huge_ numbers of > mismatch_cnt, like that: > > fter updating to Fedora 18, I get this message from all updated > systems that have RAID 6 arrays, and with _huge_ numbers of > mismatch_cnt, like that: > > # mdadm -q --detail /dev/md0 > /dev/md0: > Version : 1.2 > Creation Time : Mon Jan 14 14:20:34 2013 Something is missing from this story. Was the original system created this month, and immediately upgraded? Or was there a "mdadm --create" in this story you haven't told us about? > Raid Level : raid6 > Array Size : 1459617792 (1392.00 GiB 1494.65 GB) > Used Dev Size : 243269632 (232.00 GiB 249.11 GB) > Raid Devices : 8 > Total Devices : 8 > Persistence : Superblock is persistent > > Update Time : Sun Jan 27 02:27:28 2013 > State : clean > Active Devices : 8 > Working Devices : 8 > Failed Devices : 0 > Spare Devices : 0 > > Layout : left-symmetric > Chunk Size : 16K > > Name : XXX:0 (local to host XXX) > UUID : da015f96:138b37bf:d5ef71dc:8970ab15 > Events : 8 > > Number Major Minor RaidDevice State > 0 8 49 0 active sync /dev/sdd1 > 1 8 65 1 active sync /dev/sde1 > 2 8 81 2 active sync /dev/sdf1 > 3 8 97 3 active sync /dev/sdg1 > 4 8 113 4 active sync /dev/sdh1 > 5 8 129 5 active sync /dev/sdi1 > 6 8 145 6 active sync /dev/sdj1 > 7 8 161 7 active sync /dev/sdk1 > # cat /sys/block/md0/md/mismatch_cnt > 362732152 > > > This is with mdadm v3.2.6 (mdadm-3.2.6-7.fc18.x86_64); except for the > huge values of mismatch_cnt, I see no other indications for errors on > the disk drives, RAID arrays or the file systems on top of these. > > Is this some known (and hopefully harmless), issue, or must I worry > about our data? I would be worried, but there's not enough information here to say. Please share the output of "mdadm -E /dev/sd[defghijk]1". Please also explain/share what you've done to conclude the filesystem is error-free. Phil -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
