Re: [smartmontools-support]question regarding unknown_attribute

[Bruce A. <ba...@gr...>]

Hi Brett,

On Tue, 17 Feb 2004, Brett Russ wrote:

> I see the following at the end of my attrib. data struct. dump:
> 
>   99 Unknown_Attribute       0x0004   253   253   000    Old_age
> Offline      -       0
> 100 Unknown_Attribute       0x0004   253   253   000    Old_age 
> Offline      -       0
> 101 Unknown_Attribute       0x0004   253   253   000    Old_age 
> Offline      -       0
> 
> I see that these 3 entries make up the difference between the 27
> attributes described in Maxtor's SMART users guide (rev C, May 2002)
> and the hard coded display of 30 in the code.

That's not a correct description of the situation.  It's not that these 3
Attributes are not being used.  They are.  It's simply that Maxtor
considers them to be proprietary, and won't tell us what they mean or how
to interpret them (I've asked).

> Question is, can this be cleaned up such that unknown attributes are not 
> displayed or is this left in here intentionally in case the code is out 
> of sync with a vendor's attribute definitions?  

Neither.  They are left because they are valid attributes.  It just that
we have no name for them and don't know how to interpret them.

The SFF-8035i and ATA specs are clear about what to have in the Attribute
table if a vendor wants less than 30 Attributes.  They have to zero fill
the corresponding data structures. Maxtor has NOT done that for these
three Attributes because they really do exist and have meanings.  Its just
that no one (at Maxtor) will tell us what those meanings are.

> I wonder if it's possible for the stale IDs to accidentally map to
> valid attrib. names and cause incorrect output?

No.

By the way, I'd be interested to see the Maxtor's SMART users guide (rev
C, May 2002).  Can you provide a URL or send me a copy?

Bruce