I wrote a small script to handle my zfs backups. When i run it by hand, it works well:
/root/bin/zfs-backup -k 7 -p zfs-auto-snap_daily -r vm/containers tank/backups
But running it in cron like so, throws an error "The file system 'vm/containers' doesn't exists."
30 0 * * * root /root/bin/zfs-backup -k 7 -p zfs-auto-snap_daily -r vm/containers tank/backups