HD SMART question

[David Rosenstrauch]

Tom Metro wrote:
> David Rosenstrauch wrote:
>> I...decide to check out the drive's status in smartctl before I start
>> dumping data onto it. ...it looks like the drive is showing a load of
>> smart errors in the "raw read error rate" and the "seek error rate" -
>> and that they're increasing!
> ...
>> ATTRIBUTE_NAME      VALUE WORST THRESH WHEN_FAILED RAW_VALUE
>> Raw_Read_Error_Rate 100   100   006        -       66806
>> Raw_Read_Error_Rate 100   100   006        -       74278
> 
> Yeah, but you're looking at the raw value. As I recall, the raw value is 
> generally meaningless, as the mechanism by which it gets converted into 
> the "cooked" value is proprietary to the manufacturer. The WD drive may 
> have a similar raw internal counter that they're just choosing not to 
> expose.
> 
> Notice that the cooked values are consistent between runs, and appear to 
> be at their factory initialized values.
> 
> Read through the smartd FAQ (http://smartmontools.sourceforge.net/). I 
> believe it addresses this point on raw vs. cooked values.
> 
> 
>> Self-tests seem to succeed without error
> 
> Because nothing has failed yet. Notice the WHEN_FAILED column just shows 
> "-". Until the cooked value for that setting gets below 6, it isn't 
> considered a failed state. (Some smart attributes decrement.)
> 
> 
>> can I trust this new drive with my backup data, or is this
>> new one a lemon too...
> 
> See the "drive burn-in" thread from last Fall:
> http://www.nabble.com/hard-drive-burn-in-td19576394s24859.html
> 
> I'd recommend using some of the techniques recommended there (some of 
> which you're already doing) to exercise the drive for a week or so 
> before you trust it with data. And of course, make sure you've set up 
> smartd to send you notifications if anything changes.
> 
>  -Tom

Very helpful!  Thanks much!

DR