SMART: disk problems on RAIDZ1 pool: (ada6:ahcich6:0:0:0): CAMstatus: ATA Status Error

Willem Jan Withagen wjw at
Thu Dec 14 11:05:20 UTC 2017

On 13/12/2017 17:47, Rodney W. Grimes wrote:
>> On Tue, 12 Dec 2017 14:58:28 -0800
>> Cy Schubert <Cy.Schubert at> wrote:
>> I think people responding to my thread made it clear that the WD Green
>> isn't the first-choice-solution for a 20/6 (not 24/7) duty drive and
>> the fact, that they have serviced now more than 25000 hours, it would
>> be wise to replace them with alternatives.
> I think someone had an apm command that turns off the head park,
> that would do wonders for drive life.   On the other hand, I think
> if it was my data and I saw that the drive had 2M head load cycles
> I would be looking to get out of that driv with any data I could
> not easily replace.  If it was well backed up or easily replaced
> my worries would be less.

WD made their first series of Green disks green by aggressively turning 
them into sleep state. Like when few secs there was nog activity they 
would park the head, spin it down, and sleep the disk...
Access would need to undo the whole series of command.

This could be reset by writing in one of the disks registers. I remember 
doing that for my 1,5G WDs (WD15EADS from 2009). That saved a lot of 
startups. I still have 'm around, but only use them for things that are 
not valuable at all. Some have died over time, but about half of them 
still seem to work without much trouble.

WD used to have a .exe program to actually do this. But that did not
work on later disks. And turning things of on those disks was 
impossible/a lot more complex.

This type of disk worked quite a long time in my ZFS setup. Like a few 
years, but I turned parking of as soon as there was a lot of turmoil 
about this in the community.
Now I using WD reds for small ZFS systems, and WD red Pro for large 
private storage servers. Professional server get HGST He disks, a bit 
more expensive, but very little fallout.


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