I am expanding a raid5 array from 4 disks to 5. One of the older devices is causing traces like this to appear in /var/log/messages:
Jul 17 18:31:46 as kernel: sd 6:0:0:0: SCSI error: return code = 0x08000002
Jul 17 18:31:46 as kernel: sde: Current: sense key: Medium Error
Jul 17 18:31:46 as kernel: Additional sense: Unrecovered read error
Jul 17 18:31:46 as kernel: end_request: I/O error, dev sde, sector 800998880
Jul 17 18:31:46 as kernel: raid5:md0: read error corrected (8 sectors at 800998880 on sde)
Jul 17 18:31:46 as kernel: raid5:md0: read error corrected (8 sectors at 800998888 on sde)
Jul 17 18:31:46 as kernel: raid5:md0: read error corrected (8 sectors at 800998896 on sde)
The reshape process continues unabaited and no problems seem to be indicated.
cat /sys/block/md0/md/dev-sd?/errors
Yields:
0
0
6584
0
0
The drive with the error is of course sde. Is this something I need to be mildly worried about or extremely worried about?
Otherwise, this is a wonderful wonderful tool. Would like to convert to raid6 though ;-)