Offline uncorrectable sectors on hard drive

[Miroslav Lachman]

Patrick Proniewski wrote:

> Hi Michael,
> 
> On 4 oct. 09, at 10:50, Michael Fuckner wrote:
> 
>>> - is that "Offline uncorrectable sectors" in fact correctable? I've  
>>> found howto's for extfs and reiserfs to correct this kind of error  
>>> by remapping bad sectors, but nothing for UFS.
>>> - this error appears to have disappeared, does it mean the  harddrive 
>>> (or the fs) made the remapping by it self?
>>
>> sector errors are on the hardware, they don't deal with the  filesystem.
>>
>> Perhaps it was a once in a lifetime event, perhaps the drive is  going 
>> to die really soon.
>>
>> Please do a smartctl -t long and see if the drive has to be replaced.
> 
> 
> 
> here is the result (from `smartctl -l selftest /dev/ad6` after the  
> `smartctl -t long /dev/ad6` ):
> 
> Warning! SMART Attribute Thresholds Structure error: invalid SMART  
> checksum.
> === START OF READ SMART DATA SECTION ===
> 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%      
> 34350         -
> # 2  Short offline       Completed without error       00%      
> 34339         -
> # 3  Extended offline    Completed: read failure       20%      
> 34317         201626851
> # 4  Short offline       Completed without error       00%      
[...]
> It looks like the error is gone, but may be I'm wrong.

It is better to look at diff of Vendor Specific Attributes (smartctl -A)

You have Reallocated_Event_Count  2, so maybe bad sectors were reallocated.

Miroslav Lachman