OK, I was messing around in the box today adding two more drives and I probably hit a cable or something but maybe not. /dev/md3 was effected, but md5 built on the same drives wasn't. Possibly this has been there for a day or two and I didn't notice it. These drives are only a few days old so I hope I'm not seeing some sort of early problem. Supposedly good drives - WD 500GB RAID Edition. Currently all my RAIDs are RAID1 assembled by the kernel at boot time. I have no mdadm.conf file. mdadm is a running daemon. >From dmesg: md: considering sdb3 ... md: adding sdb3 ... md: adding sdc3 ... md: adding sda3 ... md: created md3 md: bind<sda3> md: bind<sdc3> md: bind<sdb3> md: running: <sdb3><sdc3><sda3> md: kicking non-fresh sdb3 from array! md: unbind<sdb3> md: export_rdev(sdb3) raid1: raid set md3 active with 2 out of 3 mirrors md3: detected capacity change from 0 to 53694562304 How do I go about trying to /dev/sdb3 back into the array and what sort of checking is advised when this happens before I add it back? The bad drive (sdb) doesn't look much different than the good drives. (sda shown, sdc) cruncher ~ # smartctl -A /dev/sdb smartctl 5.39.1 2010-01-28 r3054 [x86_64-pc-linux-gnu] (local build) Copyright (C) 2002-10 by Bruce Allen, http://smartmontools.sourceforge.net === START OF READ SMART DATA SECTION === SMART Attributes Data Structure revision number: 16 Vendor Specific SMART Attributes with Thresholds: ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 1 Raw_Read_Error_Rate 0x002f 200 200 051 Pre-fail Always - 0 3 Spin_Up_Time 0x0027 239 236 021 Pre-fail Always - 1016 4 Start_Stop_Count 0x0032 100 100 000 Old_age Always - 24 5 Reallocated_Sector_Ct 0x0033 200 200 140 Pre-fail Always - 0 7 Seek_Error_Rate 0x002e 200 200 000 Old_age Always - 0 9 Power_On_Hours 0x0032 100 100 000 Old_age Always - 87 10 Spin_Retry_Count 0x0032 100 253 000 Old_age Always - 0 11 Calibration_Retry_Count 0x0032 100 253 000 Old_age Always - 0 12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 22 192 Power-Off_Retract_Count 0x0032 200 200 000 Old_age Always - 12 193 Load_Cycle_Count 0x0032 200 200 000 Old_age Always - 11 194 Temperature_Celsius 0x0022 109 105 000 Old_age Always - 38 196 Reallocated_Event_Count 0x0032 200 200 000 Old_age Always - 0 197 Current_Pending_Sector 0x0032 200 200 000 Old_age Always - 0 198 Offline_Uncorrectable 0x0030 100 253 000 Old_age Offline - 0 199 UDMA_CRC_Error_Count 0x0032 200 200 000 Old_age Always - 0 200 Multi_Zone_Error_Rate 0x0008 100 253 000 Old_age Offline - 0 cruncher ~ # smartctl -A /dev/sda smartctl 5.39.1 2010-01-28 r3054 [x86_64-pc-linux-gnu] (local build) Copyright (C) 2002-10 by Bruce Allen, http://smartmontools.sourceforge.net === START OF READ SMART DATA SECTION === SMART Attributes Data Structure revision number: 16 Vendor Specific SMART Attributes with Thresholds: ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 1 Raw_Read_Error_Rate 0x002f 200 200 051 Pre-fail Always - 0 3 Spin_Up_Time 0x0027 239 235 021 Pre-fail Always - 1016 4 Start_Stop_Count 0x0032 100 100 000 Old_age Always - 24 5 Reallocated_Sector_Ct 0x0033 200 200 140 Pre-fail Always - 0 7 Seek_Error_Rate 0x002e 200 200 000 Old_age Always - 0 9 Power_On_Hours 0x0032 100 100 000 Old_age Always - 87 10 Spin_Retry_Count 0x0032 100 253 000 Old_age Always - 0 11 Calibration_Retry_Count 0x0032 100 253 000 Old_age Always - 0 12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 22 192 Power-Off_Retract_Count 0x0032 200 200 000 Old_age Always - 11 193 Load_Cycle_Count 0x0032 200 200 000 Old_age Always - 12 194 Temperature_Celsius 0x0022 108 106 000 Old_age Always - 39 196 Reallocated_Event_Count 0x0032 200 200 000 Old_age Always - 0 197 Current_Pending_Sector 0x0032 200 200 000 Old_age Always - 0 198 Offline_Uncorrectable 0x0030 100 253 000 Old_age Offline - 0 199 UDMA_CRC_Error_Count 0x0032 200 200 000 Old_age Always - 0 200 Multi_Zone_Error_Rate 0x0008 100 253 000 Old_age Offline - 0 cruncher ~ # Thanks, Mark -- 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