Got two Western Digital RED class 3 TB disks (WD30EFRX) in July 2013.

The power supply of my NAS machine died last week, but those disks still run. Fascinated!

One disk has a Power_On_Hours count of 72306, and the other one has 72305. That are 8.2 years.

Let’s have a more in-depth look (I removed some lines from the output below).

Disk 1

root@freenas:/ # smartctl -a /dev/ada4
smartctl 7.2 2021-09-14 r5236 [FreeBSD 13.1-RELEASE-p7 amd64] (local build)

=== START OF INFORMATION SECTION ===
Model Family:     Western Digital Red
Device Model:     WDC WD30EFRX-68AX9N0
Firmware Version: 80.00A80
User Capacity:    3,000,592,982,016 bytes [3.00 TB]
Sector Sizes:     512 bytes logical, 4096 bytes physical
Local Time is:    Sat Feb 10 11:51:58 2024 CET


=== START OF READ SMART DATA SECTION ===
SMART overall-health self-assessment test result: PASSED


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   179   173   021    Pre-fail  Always       -       6016
  4 Start_Stop_Count        0x0032   099   099   000    Old_age   Always       -       1015
  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   001   001   000    Old_age   Always       -       72305
 10 Spin_Retry_Count        0x0032   100   100   000    Old_age   Always       -       0
 11 Calibration_Retry_Count 0x0032   100   100   000    Old_age   Always       -       0
 12 Power_Cycle_Count       0x0032   100   100   000    Old_age   Always       -       903
192 Power-Off_Retract_Count 0x0032   200   200   000    Old_age   Always       -       69
193 Load_Cycle_Count        0x0032   200   200   000    Old_age   Always       -       945
194 Temperature_Celsius     0x0022   119   106   000    Old_age   Always       -       31
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

SMART Error Log Version: 1
No Errors Logged

SMART Self-test log structure revision number 1
Num  Test_Description    Status                  Remaining  LifeTime(hours)  LBA_of_first_error
# 1  Short offline       Completed without error       00%      6730         -
# 2  Short offline       Completed without error       00%      3753         -

Disk 2

# smartctl -a /dev/ada5
...

=== START OF INFORMATION SECTION ===
Device Model:     WDC WD30EFRX-68AX9N0
Local Time is:    Sat Feb 10 11:57:02 2024 CET
...
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       -       26
  3 Spin_Up_Time            0x0027   179   173   021    Pre-fail  Always       -       6041
  4 Start_Stop_Count        0x0032   099   099   000    Old_age   Always       -       1002
  5 Reallocated_Sector_Ct   0x0033   200   200   140    Pre-fail  Always       -       1
  7 Seek_Error_Rate         0x002e   200   200   000    Old_age   Always       -       0
  9 Power_On_Hours          0x0032   001   001   000    Old_age   Always       -       72306
 10 Spin_Retry_Count        0x0032   100   100   000    Old_age   Always       -       0
 11 Calibration_Retry_Count 0x0032   100   100   000    Old_age   Always       -       0
 12 Power_Cycle_Count       0x0032   100   100   000    Old_age   Always       -       903
192 Power-Off_Retract_Count 0x0032   200   200   000    Old_age   Always       -       56
193 Load_Cycle_Count        0x0032   200   200   000    Old_age   Always       -       945
194 Temperature_Celsius     0x0022   120   109   000    Old_age   Always       -       30
196 Reallocated_Event_Count 0x0032   199   199   000    Old_age   Always       -       1
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
...