How bad bad sectors are

Computer Hardware & Server Infrastructure Builds
1

Hi all.

So i have a ironwolf 10tb with expired warranty and 2792 bad sectors, its in a raidz2 vdev. I know its never a good sign but how urgent it is to replace it?
Currently cant afford a new one, maybe in 2 or 3 months i could get a replacement… (not seagate, 2 out of the 4 hdd i ordered died this year)

Thanks in advance! :slight_smile:

smartctl output:
root@zenifer[~]# smartctl -q noserial -a /dev/da4
smartctl 7.1 2019-12-30 r5022 [FreeBSD 12.2-RC3 amd64] (local build)
Copyright © 2002-19, Bruce Allen, Christian Franke, www.smartmontools.org

=== START OF INFORMATION SECTION ===
Model Family:     Seagate IronWolf
Device Model:     ST10000VN0004-1ZD101
Firmware Version: SC60
User Capacity:    10,000,831,348,736 bytes [10.0 TB]
Sector Sizes:     512 bytes logical, 4096 bytes physical
Rotation Rate:    7200 rpm
Form Factor:      3.5 inches
Device is:        In smartctl database [for details use: -P show]
ATA Version is:   ACS-3 T13/2161-D revision 5
SATA Version is:  SATA 3.1, 6.0 Gb/s (current: 6.0 Gb/s)
Local Time is:    Sun Oct 25 11:53:27 2020 CET
SMART support is: Available - device has SMART capability.
SMART support is: Enabled

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

General SMART Values:
Offline data collection status:  (0x82)	Offline data collection activity
					was completed without error.
					Auto Offline Data Collection: Enabled.
Self-test execution status:      ( 246)	Self-test routine in progress...
					60% of test remaining.
Total time to complete Offline 
data collection: 		(  575) seconds.
Offline data collection
capabilities: 			 (0x7b) SMART execute Offline immediate.
					Auto Offline data collection on/off support.
					Suspend Offline collection upon new
					command.
					Offline surface scan supported.
					Self-test supported.
					Conveyance Self-test supported.
					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.
					General Purpose Logging supported.
Short self-test routine 
recommended polling time: 	 (   1) minutes.
Extended self-test routine
recommended polling time: 	 ( 891) minutes.
Conveyance self-test routine
recommended polling time: 	 (   2) minutes.
SCT capabilities: 	       (0x50bd)	SCT Status supported.
					SCT Error Recovery Control supported.
					SCT Feature Control supported.
					SCT Data Table supported.

SMART Attributes Data Structure revision number: 10
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE
  1 Raw_Read_Error_Rate     0x000f   083   064   044    Pre-fail  Always       -       215608984
  3 Spin_Up_Time            0x0003   086   086   000    Pre-fail  Always       -       0
  4 Start_Stop_Count        0x0032   100   100   020    Old_age   Always       -       228
  5 Reallocated_Sector_Ct   0x0033   100   100   010    Pre-fail  Always       -       2792
  7 Seek_Error_Rate         0x000f   095   060   045    Pre-fail  Always       -       2867265464
  9 Power_On_Hours          0x0032   068   068   000    Old_age   Always       -       28103 (57 91 0)
 10 Spin_Retry_Count        0x0013   100   100   097    Pre-fail  Always       -       0
 12 Power_Cycle_Count       0x0032   100   100   020    Old_age   Always       -       97
184 End-to-End_Error        0x0032   100   100   099    Old_age   Always       -       0
187 Reported_Uncorrect      0x0032   100   100   000    Old_age   Always       -       0
188 Command_Timeout         0x0032   100   100   000    Old_age   Always       -       0
189 High_Fly_Writes         0x003a   083   083   000    Old_age   Always       -       17
190 Airflow_Temperature_Cel 0x0022   059   051   040    Old_age   Always       -       41 (Min/Max 26/44)
191 G-Sense_Error_Rate      0x0032   094   094   000    Old_age   Always       -       13976
192 Power-Off_Retract_Count 0x0032   100   100   000    Old_age   Always       -       16
193 Load_Cycle_Count        0x0032   100   100   000    Old_age   Always       -       293
194 Temperature_Celsius     0x0022   041   049   000    Old_age   Always       -       41 (0 23 0 0 0)
195 Hardware_ECC_Recovered  0x001a   031   001   000    Old_age   Always       -       215608984
197 Current_Pending_Sector  0x0012   100   100   000    Old_age   Always       -       0
198 Offline_Uncorrectable   0x0010   100   100   000    Old_age   Offline      -       0
199 UDMA_CRC_Error_Count    0x003e   200   200   000    Old_age   Always       -       0
200 Multi_Zone_Error_Rate   0x0023   100   100   001    Pre-fail  Always       -       0
240 Head_Flying_Hours       0x0000   100   253   000    Old_age   Offline      -       28005 (178 91 0)
241 Total_LBAs_Written      0x0000   100   253   000    Old_age   Offline      -       55261933697
242 Total_LBAs_Read         0x0000   100   253   000    Old_age   Offline      -       187459220269

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  Extended offline    Self-test routine in progress 60%     28103         -
# 2  Short offline       Completed without error       00%     27923         -
# 3  Short offline       Completed without error       00%     27755         -
# 4  Short offline       Completed without error       00%     27587         -
# 5  Extended offline    Completed without error       00%     27530         -
# 6  Short offline       Completed without error       00%     27419         -
# 7  Extended offline    Completed without error       00%     26626         -
# 8  Short offline       Completed without error       00%     26412         -
# 9  Short offline       Completed without error       00%     25668         -
#10  Short offline       Completed without error       00%     24948         -
#11  Extended offline    Completed without error       00%     24418         -
#12  Short offline       Completed without error       00%     24036         -
#13  Extended offline    Completed without error       00%     24007         -
#14  Short offline       Completed without error       00%     23317         -
#15  Short offline       Completed without error       00%     22574         -
#16  Extended offline    Completed without error       00%     22261         -
#17  Short offline       Completed without error       00%     21878         -
#18  Short offline       Completed without error       00%     21134         -
#19  Short offline       Completed without error       00%     20390         -
#20  Short offline       Completed without error       00%     19670         -
#21  Short offline       Completed without error       00%     18928         -

SMART Selective self-test log data structure revision number 1
 SPAN  MIN_LBA  MAX_LBA  CURRENT_TEST_STATUS
    1        0        0  Not_testing
    2        0        0  Not_testing
    3        0        0  Not_testing
    4        0        0  Not_testing
    5        0        0  Not_testing
Selective self-test flags (0x0):
  After scanning selected spans, do NOT read-scan remainder of disk.
If Selective self-test is pending on power-up, resume after 0 minute delay.
2

The urgency of replacing the drive comes down to the value you place on having the data and of course if you have it backed up. That many bad sectors does not sound good to me.

3

Well i do backup the important stuff but it would be a PITA to reacquire the rest. Is there any chance that a failed hdd could corrupt a 5 drive raidz2 vdev?

/EDIT
One thing i find interesting is that smartd did not log the bad sector events and dashboard says no disks with errors in the pool…

4

Interesting, the extended offline test passed without errors… :thinking: (bad sector count still 2792)

5

In my mind, the marking of the sectors as bad is done at the HDD firmware level. This way there might be no read or write errors perceivable by the upper software levels. ZFS could be oblivious to the bad sectors as it produced no read or write errors. Can someone uphold my theory?

6

Not sure I can uphold your theory due to competence (or lack of) but I did have a a 8TB drive that had a few bad sectors that 2 NAS units I have refused to format however my desktop running proxmox eagerly accepted.

7

Sounds like a reasonable explanation.

Speaking about explanations. I just dont get it how 2 out of 4 drives (ordered them at the same time) can crap out right around the time when warranty expires, it seems a bit too much to be a coincidence…

8

@Lockon_Stratos
I’ve had 3 WD Red NAS drives die within about 3 months of each other – really kind of makes me angry. Clearly a bad batch. All died within 3 months of warranty expiring. Almost seems like planned obsolence. I can see no drive manufacturer seems immune to the problem. Probably not going with WD next time however.

With that many bad sectors — its just a matter of time until problems start going. I had a raidz2 array and I ran with a degraded array down 1 drive for a couple of weeks until replacement. Hopefully you’re array will hold out for a few months however plan for a replacement whenever you can – more of a question of when than if.

9

Just as a closing update, i got the replacement hdd (HUH721010ALE600) yesterday, popped it right in and truenas finished resilvering in about 6 hours (5disk raidz2). The synology i used as the main NAS in the past needed a full day for a 4 disk raid5 array…