I thought this one was going to be a challenge to set up but it turns out it’s set up automatically to scrub the disks on the server Sunday of every month. The important files for this setup are:
/etc/cron.d/zfsutils-linux /usr/lib/zfs-linux/scrub
The file in cron.d sets the schedule and calls the scrub script which actually performs the scrub. The scrub script is quite clever, it picks all the healthy pools and scrubs them it will also not try and scrub a pool that’s already being scrubbed. The one thing it doesn’t appear to do is report any issues found during the scrub. This is somewhat visible through the GUI but an email would be nice.