Reallocated Sectors

[Chris Pollard]

I have a Samsung HD154UI which has had 2 reallocated sectors appear over the last month...  anyone know if I'll be able to RMA it?  Its still under warranty but I guess they could argue that its normal.

[prostuff1]

I have a Samsung HD154UI which has had 2 reallocated sectors appear over the last month...  anyone know if I'll be able to RMA it?  Its still under warranty but I guess they could argue that its normal.

 

No, that is no were near enough to worry about.  Now if the count goes up dramatically in a very short period then it would be something to worry about.

[betaman]

How many ATA errors does the drive have and have they increased dramatically?  I was able to RMA a Seagate drive due to exponential increases in read errors in a short period of time.  I've also found that if the mfg requires you run a utility before RMA, tell them the disk is formatted ReiserFS and you have SMART report data telling you the drive is getting worse.

[Chris Pollard]

Here's the SMART output :-

 

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   100   100   051    Pre-fail  Always       -       6
 3 Spin_Up_Time            0x0007   069   069   011    Pre-fail  Always       -       10010
 4 Start_Stop_Count        0x0032   100   100   000    Old_age   Always       -       488
 5 Reallocated_Sector_Ct   0x0033   100   100   010    Pre-fail  Always       -       2
 7 Seek_Error_Rate         0x000f   100   100   051    Pre-fail  Always       -       0
 8 Seek_Time_Performance   0x0025   100   100   015    Pre-fail  Offline      -       0
 9 Power_On_Hours          0x0032   099   099   000    Old_age   Always       -       3461
10 Spin_Retry_Count        0x0033   100   100   051    Pre-fail  Always       -       0
11 Calibration_Retry_Count 0x0012   100   100   000    Old_age   Always       -       0
12 Power_Cycle_Count       0x0032   100   100   000    Old_age   Always       -       52
13 Read_Soft_Error_Rate    0x000e   100   100   000    Old_age   Always       -       0
183 Unknown_Attribute       0x0032   100   100   000    Old_age   Always       -       0
184 Unknown_Attribute       0x0033   100   100   000    Pre-fail  Always       -       0
187 Reported_Uncorrect      0x0032   100   100   000    Old_age   Always       -       0
188 Unknown_Attribute       0x0032   100   100   000    Old_age   Always       -       0
190 Airflow_Temperature_Cel 0x0022   079   066   000    Old_age   Always       -       21 (Lifetime Min/Max 12/25)
194 Temperature_Celsius     0x0022   079   065   000    Old_age   Always       -       21 (Lifetime Min/Max 12/26)
195 Hardware_ECC_Recovered  0x001a   100   100   000    Old_age   Always       -       538921367
196 Reallocated_Event_Count 0x0032   100   100   000    Old_age   Always       -       2
197 Current_Pending_Sector  0x0012   100   100   000    Old_age   Always       -       0
198 Offline_Uncorrectable   0x0030   100   100   000    Old_age   Offline      -       0
199 UDMA_CRC_Error_Count    0x003e   100   100   000    Old_age   Always       -       0
200 Multi_Zone_Error_Rate   0x000a   100   100   000    Old_age   Always       -       11
201 Soft_Read_Error_Rate    0x000a   100   099   000    Old_age   Always       -       0

 

The unaid main page lists 22 errors and I see some ATA errors relating to this drive in the syslog.  Oh and both reallocated sectors appeared right after the monthly parity check.... guessing a third will appear this month

[Joe L.]

I have a Samsung HD154UI which has had 2 reallocated sectors appear over the last month...  anyone know if I'll be able to RMA it?  Its still under warranty but I guess they could argue that its normal.

 

No, that is no were near enough to worry about.  Now if the count goes up dramatically in a very short period then it would be something to worry about.

I agree... nowhere near enough to worry about.  if you suddenly see hundreds, then RMA.  One or two here and there... no issue, the drive typically has thousands of spare sectors.

[betaman]

Yeah, sometimes ignorance is bliss!  Before these SMART reports and the syslog in UNRAID I would've never known my drive was having any "issues".  Do you have any similar drives in your array?  How do the SMART reports compare?  In my case, the drive only had 60 hours runtime.  I would imagine with almost 3500 hours that a reallocated sector here or there is not the end of the world but I'm sure that doesn't make you feel any better!  I would continue to monitor it against the warranty expiration to see if the errors continue and then see what you can do.  It does seem like there is a threshold where the errors begin to matter and 2 reallocated sectors is probably not very close to it!

[Chris Pollard]

Just a shame its my parity disk really.  Means I have to swap it to get peace of mind regardless of whether I RMA it. 

 

I've got a few other of the same model with similar runtimes, none of those have any reallocated sectors.

[SSD]

While a few reallocated sectors is no big deal, experiences here show that frequently the numbers grow and grow. Kind of like pulling on a thread and winding up unraveling a whose garment. I'd suggest you start to run frequent parity checks (every day or two) and monitor the number. If they stay staedy for 3-4 days straight, I'd start to feel confident that the drive is solid. But if each run produces a few more, I would not trust it. Keeping the smart reports demonstrating the degradation should help make a case for RMA'ing the drive.

[purko]

Disks have been known to show a bad sector or two, and then work many years with no more problems whatsoever.

 

So, like others suggested, don't worry about this at all.

 

But keep an eye on the disk, and if the number of reallocated sectors starts increasing, then you should start worrying about it.

 

 

[Chris Pollard]

1st drive I've ever owned thats developed reallocated sectors without me doing something stupid to it.  The drives from my old windows 2000 file server have 40000+ hours on them with no errors (well apart from one I dropped ).

[Joe L.]

Older drives did not pack the bits on the platters so densely. Newer disks will suffer more read errors... expect them...

  (We don't see most of them, since the disk uses its own internal checksums to detect them...) 

Some drives report the raw read error rate in a SMART report, others hide that data from us.. 

[Chris Pollard]

Life was so much easier when I could keep all my files on three 120gb disks with software raid 5

[wholly]

At least until one of those drives failed or you outgrew the array!

[Joe L.]

At least until one of those drives failed or you outgrew the array!

Or drop the disk drive.    ;D

 

Actually, many of today's disks are pretty good about handling physical abuse. (as long as they are not powered up and spinning at the time you drop them)

[Chris Pollard]

Well I ran another Parity check and another reallocated sector appeared.  3 Parity checks 3 new reallocated sectors.  Think I'll buy a new drive and then thrash this one with the pre-clear script until they stop appearing.

[Joe L.]

Well I ran another Parity check and another reallocated sector appeared.  3 Parity checks 3 new reallocated sectors.  Think I'll buy a new drive and then thrash this one with the pre-clear script until they stop appearing.

Did you pre-clear it initially?

[Chris Pollard]

Did you pre-clear it initially?

 

No, its my parity drive since I first setup unRAID so these are definitely new.

[betaman]

Joe means did you run the pre-clear script on this drive before adding it to your array?

[Chris Pollard]

Its my parity drive... not much point pre-clearing it.  (unless I'm missing something basic?)

[purko]

Its my parity drive... not much point pre-clearing it.  (unless I'm missing something basic?)

 

"pre-clearing" it would give you the chance to seriously exercise your disk before assigning it anywhere in your server.

 

 

[Chris Pollard]

oh i see,  before unraid it was in another array so it had plenty of uptime.

[aiden]

"pre-clearing" it would give you the chance to seriously exercise your disk before assigning it anywhere in your server.

 

It also gives you some very interesting insight into the performance of that drive, and gives the SMART controller some very good baseline information as it works the entire disk in the cycle.  I have 2 TB drives running 10 pre-clear cycles that will take a total of around 280 hours to complete.  Although both disks are exactly the same model with the same specifications, one drive is showing about 1% higher throughput than the other.  It's not much, but I know which one will be my parity drive. 

[Chris Pollard]

for the record this drive reached 15 re-allocated sectors with no sign of improvement, I RMA'd to Samsung (UK) and they replaced with a new drive with a 3 day turn around.  (Sent drive on Monday,  New drive arrived Wednesday)