CK nibbana at
Sat Mar 28 05:04:19 UTC 2015

Regarding the unexpected loss of files from the filesystem under various
loads, is the appended 'smartctl' data sufficient to make the determination
that the loss of files while the operating system is in use could be due to
the condition of the drive?

I didn't think so at first, because:

1)  I would expect a FreeBSD error to the effect of "unable to read/write
    /dev/ada0" or "block checksum does not match block data".

2)  I would expect that all data read/written to from a drive is verfied to be
    correct by FreeBSD with checksums, and that it is guaranteed to be correct
    if there are no serious and fatal errors reported by the operating system.

But I may be wrong in these assumptions.  Anybody know for sure? I have never
seen FreeBSD report any filesystem r/w errors. My past experience has only
taught me that when a drive begins to make very bad noises, this generally
accompanies obvious and serious problems; and that a drive fails when the
mechanical parts fail, but not due to wear on heads/platters or other things
that may cause failures that are not detected/reported by the operating

I can't see how the loss of files could occur without FreeBSD noticing it and
reporting on it.  Does FreeBSD just trust drives to do everything correctly
at all times?


smartctl 6.2 2014-02-18 r3874 [FreeBSD 9.2-RELEASE i386] (local build)
Copyright (C) 2002-13, Bruce Allen, Christian Franke,

Model Family:     Western Digital Caviar WDxxxAB
Device Model:     WDC WD400AB-22CDB0
Serial Number:    WD-WMA9T1222658
Firmware Version: 22.04A22
User Capacity:    40,020,664,320 bytes [40.0 GB]
Sector Size:      512 bytes logical/physical
Device is:        In smartctl database [for details use: -P show]
ATA Version is:   ATA/ATAPI-5 (minor revision not indicated)
Local Time is:    Fri Mar 27 20:35:32 2015 AKDT
SMART support is: Available - device has SMART capability.
SMART support is: Enabled

SMART overall-health self-assessment test result: PASSED

General SMART Values:
Offline data collection status:  (0x84)	Offline data collection activity
					was suspended by an interrupting command from host.
					Auto Offline Data Collection: Enabled.
Self-test execution status:      (   0)	The previous self-test routine completed
					without error or no self-test has ever
					been run.
Total time to complete Offline
data collection: 		( 2376) seconds.
Offline data collection
capabilities: 			 (0x3b) SMART execute Offline immediate.
					Auto Offline data collection on/off support.
					Suspend Offline collection upon new
					Offline surface scan supported.
					Self-test supported.
					Conveyance Self-test supported.
					No Selective Self-test supported.
SMART capabilities:            (0x0003)	Saves SMART data before entering
					power-saving mode.
					Supports SMART auto save timer.
Error logging capability:        (0x01)	Error logging supported.
					No General Purpose Logging support.
Short self-test routine
recommended polling time: 	 (   2) minutes.
Extended self-test routine
recommended polling time: 	 (  42) minutes.
Conveyance self-test routine
recommended polling time: 	 (   5) minutes.

SMART Attributes Data Structure revision number: 16
Vendor Specific SMART Attributes with Thresholds:
  1 Raw_Read_Error_Rate     0x000b   200   200   051    Pre-fail  Always       -       0
  3 Spin_Up_Time            0x0007   102   099   021    Pre-fail  Always       -       3975
  4 Start_Stop_Count        0x0032   100   100   040    Old_age   Always       -       58
  5 Reallocated_Sector_Ct   0x0033   199   199   140    Pre-fail  Always       -       1
  7 Seek_Error_Rate         0x000b   200   200   051    Pre-fail  Always       -       0
  9 Power_On_Hours          0x0032   083   083   000    Old_age   Always       -       12540
 10 Spin_Retry_Count        0x0013   100   253   051    Pre-fail  Always       -       0
 11 Calibration_Retry_Count 0x0013   100   253   051    Pre-fail  Always       -       0
 12 Power_Cycle_Count       0x0032   100   100   000    Old_age   Always       -       57
196 Reallocated_Event_Count 0x0032   199   199   000    Old_age   Always       -       1
197 Current_Pending_Sector  0x0012   200   200   000    Old_age   Always       -       0
198 Offline_Uncorrectable   0x0012   200   200   000    Old_age   Always       -       0
199 UDMA_CRC_Error_Count    0x000a   200   253   000    Old_age   Always       -       0
200 Multi_Zone_Error_Rate   0x0009   200   200   051    Pre-fail  Offline      -       0

SMART Error Log Version: 1
No Errors Logged

SMART Self-test log structure revision number 1
No self-tests have been logged.  [To run self-tests, use: smartctl -t]

Selective Self-tests/Logging not supported

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