Drive Read Errors

jd1008 jd1008 at
Thu Oct 20 00:21:00 UTC 2016

It would be very useful if users were allowed the option to re-run
very low level format to remove all bad blocks from the "good" blocks
map, and create a new set of good blocks for future bad block replacement.
But of course, that would reduce the capacity (size), which would 
require that
such information be available to the computer.

But of course, manufacturers are not interested in "extending" the 
usable life of a drive :)

> On 10/17/16 13:02, Jason C. Wells wrote:
>> I recently used smartmontools long test and discovered that the drive
>> had read errors.
>> In your experience, is there any value in trying to use drive by mapping
>> bad sectors or partitioning around the errors?
> 1. There is a value if your plan to use this HDD for not important 
> data and downtime is also tolerable.
> 2. FYI: Remapping of bad sectors nowadays is done by disk's firmware. 
> To make it happen just write any data to a all bad sectors. If disk is 
> clean just run:
> dd if=/dev/zero of=/dev/adaX bs=256k
> then rerun SMART slef-test (and or dd if=/dev/adaX of=/dev/null).
> 3. Many people suggest to throw drive with bad sectors away. Such disk 
> will likely have new pending sectors in future and probability of 
> complete fail is higher than for drive with good SMART, but they can 
> work for years after bad sectors are remapped. All depends on 
> requirements for reliability and budget your have. At home I've used 
> HDD which had slef-test fail and Current_Pending_Sector > 0 in past 
> (for temporary data).
> See also:
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