[OpenIndiana-discuss] Resilver restarting on second dead drive?

[Jan Owoc]

On Thu, Feb 9, 2012 at 4:11 PM, Martin Frost <me at cs.stanford.edu> wrote:
>
> Does ZFS periodically verify hot spares?  For that matter, does it
> verify the RAIDZ disks?

I'm not aware that ZFS checks disks or portions of disks that do not
have active data. This means that if you aren't using part of a hard
drive, it isn't being checked.

In terms of verifying, every time you read data from disk, it gets
verified against a checksum that is stored in the block pointer. It's
suggested to read/verify all the data periodically (I recall reading
every week for consumer drives, every month for enterprise drives).
This is best done with the command "zpool scrub mypool". You can
(should?) put it in a cron job.

Cheers,
Jan