Periodically scrub freenas-boot

[Stijn Hendrickx]

Now that the boot device is on a ZFS partition:
Would it be useful/desirable to scrub the freenas-pool periodically (to detect boot device problems)?

I cannot add a scrub task to Storage -> Scrubs -> Add scrub to create such a task.

I hope I'm allowed to tell this and post a link: I found a nice script to include in your cron (e.g. every 15min): https://calomel.org/zfs_health_check_script.html

 

[jkh]

The system does this automatically. You don't need to schedule freenas-boot pool scrubs.

 

[Stijn Hendrickx]

OK, thanks for your reply!

 

[jmas]

Yes, there is an entry in /etc/crontab for scrubbing the freenas-boot pool every 35 days, but given the discutible quality of most pendrives, I think that a scrubbing period of 35 days may be too long. Ideally that period should be configurable (with a new parameter in System->Advanced, perhaps).

And speaking of programming periodic scrubs, I wonder why FreeNAS does not use the method provided by FreeBSD: set
daily_scrub_zfs_enable="YES" in /etc/periodic.conf, which pools to scrub using daily_scrub_zfs_pools and the scrubbing period for each pool using daily_scrub_zfs_${poolname}_threshold. I suppose that there is a reason; just wondering.