Bad sectors: how bad can it be

Michaël Grünewald michaelgrunewald at
Wed Oct 28 21:06:42 UTC 2009

Hello David,

thank you for your comments,

David N wrote:
> 2009/10/29 Michaël Grünewald <michaelgrunewald at>:
>> SMART Self-test log structure revision number 1
>> Num  Test_Description    Status                  Remaining LifeTime(hours)
>>  LBA_of_first_error
>> # 1  Extended offline    Completed without error       00%       458     -
>> # 2  Extended offline    Aborted by host               70%       456
> If your smartctl says it has used up a spare block
> (Reallocated_Sector_Ct), replace the drive ASAP. The drives will tend
> to get more and more bad blocks after the the first one is found,
> usually because the head is damaging the disks or the head itself is
> damaged, or other reasons. If its under warranty they usually replace
> is, talk to the manufacturer before hand.

I have Reallocated_Sector_Ct=0 for the faulty drive. Where can I find a 
key fo reading all the other exciting numbers listed under the banner

``SMART Attributes Data Structure revision number: 10
   Vendor Specific SMART Attributes with Thresholds:'' ?

On the hard-drive I use for my backups, a SAMSUNG HD501LJ,  all the 
numbers I read looks fine to me, but I want to be sure. Thus it would be 
nice have a key for the table that `smartctl -a /dev/ad6' outputs. My 
two other drives, I use to store my OS and my data, are MAXTOR 
STM3250820AS (I do not have a RAID setup, it just happens that I have 
twin hard drives). They both have `Reallocated_Sector_Ct=0' but have 
positive `Raw_Read_Error_Rate', `Seek_Error_Rate'. Additionally, the 
faulty drive has positive 
`Reported_incorrect=119',`Current_Pending_Sector=4294967295' and 

As looking for hints on google leads to many threads discussing 
hard-drive failures, I did not find what a pleasant description of the 
signification of these numbers.
Kind regards,

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