Confused about Surface Test Results
Confused about Surface Test Results
I have a 2 TB hard drive that shows health is 0% and ready to fail (it has almost 4,000 bad sectors). I ran the surface test for drive regeneration. It took 83 hours to run the test and the results came back 100% perfect - no new problems found. I tried offsetting the number of bad sectors and the health is still 0%. Why can I not get the health back to 100% by offsetting the number of bad sectors?
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hdsentinel
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Re: Confused about Surface Test Results
Basically, as you may see in the text description, there are lots of errors reported for this hard disk drive. I can recommend what the software suggests:
> Replace hard disk immediately.
> It is recommended to backup immediately to prevent data loss.
When 0% health displayed, it means that the hard disk has too many errors - and the error-level threshold (specified by the manufacturer) already reached, so the hard disk drive considered as "bad" and could be replaced under warranty.
The "bad sectors" reported in the text description are no longer used by the hard disk: they are already reallocated.
So the spare area is used for all reads and writes targeting those bad sectors. This means that disk surface tests (even the tests in Hard Disk Sentinel) do not access those sectors, but tests the remaining data area and the spare area.
This is good, as this way you can be sure that the original (bad) area does not contain important data and can't risk data loss.
This is why the detected and reported bad sectors can NEVER cause problems, regardless of their position because that problematic area is never used any more. This is why manufacturers (really shame but work this way) "allow" some bad sectors and may not offer warrantly replacement until the error-level threshold reached.
If your hard disk already found and reallocated all possible such bad sectors, it is possible that the surface test show that the data area is usable.
We may use the tests of Hard Disk Sentinel (for example Disk menu -> Surface test -> Reinitailise disk surface test) to force the hard disk to perform the reallocation of sectors if required (and improve the usability of the drive in general). This is called regeneration of hard disk drives.
But because of the high number of problems, there is very high chance that more sectors (usually neighbour sectors of the original bad ones) may fail. Maybe today or tomorrow - maybe after more time, but usually more and more problems will be reported, until the spare area will be full and/or the hard disk fail completely.
Many hard disks may fail even before this point, even before reaching the error-level threshold. That's why it is important to be notified about possible degradations, new problems, decreased health.
In this situation, you may ask for warranty replacement (if the hard disk still has warranty) because the hard disk is considered "bad". For a such hard disk, new operating system installations may not be possible at all and it is possible that the computer even displays a warning notification before starting the operating system, indicating that hard disk drive failure may occur soon.
Generally, the Offsets are designed to acknowledge minor problems and reset the error counter, as then Hard Disk Sentinel only shows possible new problems and no longer displays issues related to the past.
But when the error-level threshold reached (the health is 0 %), the offsets no longer work as you can see: even if the error counter cleared, the health remains at 0%, exactly to prevent showing "perfect" status for an almost dead hard disk drive.
> Replace hard disk immediately.
> It is recommended to backup immediately to prevent data loss.
When 0% health displayed, it means that the hard disk has too many errors - and the error-level threshold (specified by the manufacturer) already reached, so the hard disk drive considered as "bad" and could be replaced under warranty.
The "bad sectors" reported in the text description are no longer used by the hard disk: they are already reallocated.
So the spare area is used for all reads and writes targeting those bad sectors. This means that disk surface tests (even the tests in Hard Disk Sentinel) do not access those sectors, but tests the remaining data area and the spare area.
This is good, as this way you can be sure that the original (bad) area does not contain important data and can't risk data loss.
This is why the detected and reported bad sectors can NEVER cause problems, regardless of their position because that problematic area is never used any more. This is why manufacturers (really shame but work this way) "allow" some bad sectors and may not offer warrantly replacement until the error-level threshold reached.
If your hard disk already found and reallocated all possible such bad sectors, it is possible that the surface test show that the data area is usable.
We may use the tests of Hard Disk Sentinel (for example Disk menu -> Surface test -> Reinitailise disk surface test) to force the hard disk to perform the reallocation of sectors if required (and improve the usability of the drive in general). This is called regeneration of hard disk drives.
But because of the high number of problems, there is very high chance that more sectors (usually neighbour sectors of the original bad ones) may fail. Maybe today or tomorrow - maybe after more time, but usually more and more problems will be reported, until the spare area will be full and/or the hard disk fail completely.
Many hard disks may fail even before this point, even before reaching the error-level threshold. That's why it is important to be notified about possible degradations, new problems, decreased health.
In this situation, you may ask for warranty replacement (if the hard disk still has warranty) because the hard disk is considered "bad". For a such hard disk, new operating system installations may not be possible at all and it is possible that the computer even displays a warning notification before starting the operating system, indicating that hard disk drive failure may occur soon.
Generally, the Offsets are designed to acknowledge minor problems and reset the error counter, as then Hard Disk Sentinel only shows possible new problems and no longer displays issues related to the past.
But when the error-level threshold reached (the health is 0 %), the offsets no longer work as you can see: even if the error counter cleared, the health remains at 0%, exactly to prevent showing "perfect" status for an almost dead hard disk drive.