Maybe the message in one or other of the cases should be different?


On Fri, Apr 02, 2010 at 11:54:53AM +0100, Stuart Henderson wrote:
quoted text
> On 2010/04/02 11:54, Vincent wrote:
> > Hi folks,
> > 
> > One of my servers has a problem with its harddrive. To receive a warning on
> > harddrive failures, I usually have the following as a cronjob:
> > /sbin/atactl /dev/wd0c smartstatus >> /dev/null 2>&1
> > The output of /sbin/atactl /dev/wd0c smartstatus on that server is: No SMART
> > threshold exceeded
> 
> This issues SMART RETURN STATUS, and checks the return code from the drive.
> 
> http://www.t13.org/Documents/UploadedDocuments/project/d1321r3-ATA-ATAPI-5.pdf
> see section 8.41.7 (type '218g' if you're reading in mupdf..)
> 
> The drive is meant to make an intelligent decisions based on it's own
> interpretation of the attributes as to what return code it should use
> for this. If this comes back clean, the drive thinks that it is ok.
> 
> > However, if i use: /sbin/atactl /dev/wd0c readattr
> > I receive this:
> > Attributes table revision: 16
> > ID      Attribute name                  Threshold       Value   Raw
> >  1     Raw Read Error Rate               16            100
> > 0x000000000000
> >  2     Throughput Performance         50            100     0x000000000000
> >  3     Spin Up Time                      	24            120
> > 0x000300a600a5
> >  4     Start/Stop Count                  	 0            100
> > 0x00000000001b
> >  5    *Reallocated Sector Count        5              1     0x00000000075b
> >  7     Seek Error Rate                   	67            100
> > 0x000000000000
> > ...
> > One or more threshold values exceeded!
> 
> This does a SMART READ DATA and SMART READ THRESHOLD (not in the version
> of the spec in the pdf I found; register value 0xD1) and makes a simple
> comparison of the values.
> 
> > I had a look at atactl.c and noticed, that the threshold check is completely
> > different! [1]
> 
> I don't see a problem with this. In one you're asking the drive to carry
> out one specific command and return the result; in the other you're asking
> it to carry out a different command and return the result (the threshold
> comparison in that one is something extra atactl does).
> 
> The main value I place in the SMART commands is that they let you do
> some basic tests so you can decide if it's worth rebooting to run the
> vendor tools if you want to return a drive...