[smartmontools-support] Smart logs for WDC drives (YS2500)

[Tony L. <la...@ch...>]

Bruce

I have made some progress-thanks to 3ware and to you; but no thanks to =
WDC.
I asked for a description of the vendor-specific attributes and they
refused. Nice. But I think I understand a little better, nevertheless. =
It
seems that the spin up time is encoded via 3 16 bit integers (base10). =
In
that format the lowest (I think) bits encode the spin up time, the next =
16
have something which smartmontools reports as Average but which may not =
be.
In most cases its zero but for some drives it is 7 and occasionally 8. =
It
would be useful to know what this means. The upper 16 bits always are =
zero
(it seems). Also the spin up time does not seem to be active for the =
first
few spin ups. I have 5 start ups on one drive and its still not =
reporting a
spin up time.

I tried using a separate 300W PS to power a single drive with a long =
spin up
time. It made no difference to the SMART log so in the end I don't think
power is the issue. If I move the drive to a different box the "Average"
integer gets reset to zero and I get a normal spin up time. I put one =
such
drive back on the RAID array with the normal PS. It now seems happy,
reporting a normal spinup time with the 2nd integer still on 0. It =
reports a
failed spin up in the past but is OK (<4 s) now. I am going to try the =
same
process with the other 2 "slow" drives.

My best guess is that we had a couple a bad power connectors which =
caused
some failed or near failed spin ups. For some reason the SMART log is =
not
forgetting about this-I suspect this is signified by the second integer.
When you change hardware it does reset the spinup time so then it seems =
OK.

Not sure if this makes any sense-but I have learnt something about
smartmontools.

Tony


-------------------------------
Tony Ladd
Professor, Chemical Engineering
University of Florida
PO Box 116005
Gainesville, FL 32611-6005

Tel: 352-392-6509
FAX: 352-392-9513
Email: tl...@ch...
Web: http://ladd.che.ufl.edu=20