new re-RMA disk, smartmontools shows Power-off_retract_count > 65536+ but other 'Count' values are < 5-10

[Veek]

I got a re-RMA disk from WD/HGST yesterday. I ran
smartmontools -a
It showed:
​http://storage3.static.itmages.com/i/18/0110/h_1515564294_4418639_a4ca5b7dc5.png
which is consistent with new disk - all 'Counts' are close to 0 indicating it's new and unused.

Then I ran badblocks, eventually I noticed:
​http://storage6.static.itmages.com/i/18/0110/h_1515564374_9537536_ec3d5ce9e6.png

The Power Off Retract count shows 65537 but every other count value is < 10. Also,
The retract count increments by 1 or 2, as expected, whenever I reboot. Additionally
I've been running badblocks and ddrescue on the disk and have not seen sudden jumps in
the Retract Count since that spike.

How is the retract count changing value so suddenly to such a high value? Is it a bug in
smartmontools - the first time i ran it (intermittent error)? Or is the drive firmware buggy
and lying about results?

Is it a HGST/WD RMA-weasle issue - the first RMA disk was total crud so I had to return that - is this disk going to magically fail after 8mo of warranty has expired?

[Veek]

what is interesting is how it spiked to a power of 2: 2^{16 = 65536. However 65540 - 65535 = 5 and that doesn't match up to any other count. What's going on?}

The odds of me using a brand new drive in less than 24 hrs, or an error in the disk, that causes the heads to retract exactly 6553X times (occurring close to a power of 2^{16) ought to be low .}

However if the firmware for the drive, has some code, to update SMART after the firmware detects some use, the lazy programmer could update a 16bit register to 'fffX' and SMART would instantly show 65536 or thereabouts - to what end??

[Veek]

my hdparm/smartmontools outputs on the pristine re-RMA disk

[Christian Franke]

The six raw value bytes of this attribute possibly encode more than one value. The meaning is unknown unless the vendor provides a documentation. Try -v 192,raw16, -v 192,raw8 or -v 192,hex48 options for different print formats. We could possibly add such an option to the HGST Z5K500 drive database entry.

This is neither a smartctl bug nor a firmware bug. Smartctl simply prints what the drive returns in SMART DATA block. The meaning of specific SMART Attributes were never part of ATA standards.

Please provide smartctl -x ... output of this drive as an attachment. It may contain Device Statistics which is part of ATA standards.

[Veek]

smartctl -x /dev/sda

[Veek]

smartctl -v 192,raw16 /dev/sda

192 Power-Off_Retract_Count 0x0032 100 100 000 Old_age Always - 0 1 6

smartctl -a -v 192,raw8 /dev/sda
192 Power-Off_Retract_Count 0x0032 100 100 000 Old_age Always - 0 0 0 1 0 6

smartctl -a -v 192,hex48 /dev/sda
192 Power-Off_Retract_Count 0x0032 100 100 000 Old_age Always - 0x000000010006

(I'm liking the idea of '6' - i'll call their tech support and ask in a day or two) many thanks!