vfs.root.mountfrom="zfs:hpelitebook8570p/ROOT/2017-07-14-17"

root@momh167-gjp4-hpelitebook8570p-freebsd:~ # grep vfs.root.mountfrom /boot/loader.conf
vfs.root.mountfrom="zfs:hpelitebook8570p/ROOT/2017-07-14-17"
root@momh167-gjp4-hpelitebook8570p-freebsd:~ # beadm list
BE            Active Mountpoint  Space Created
default       R      -            8.5G 2017-07-07 10:50
2017-07-14-10 -      -          345.3M 2017-07-14 10:29
2017-07-14-17 N      /            1.1G 2017-07-14 17:40
root@momh167-gjp4-hpelitebook8570p-freebsd:~ # zfs list -t snapshot
NAME                                                      USED  AVAIL  REFER  MOUNTPOINT
hpelitebook8570p/ROOT/2017-07-14-10@2017-07-14-17:40:47   692K      -  8.79G  -
hpelitebook8570p/ROOT/default@2017-07-14-10:29:16         656K      -  8.49G  -
hpelitebook8570p/poudriere/jails/current@clean            256K      -   948M  -
root@momh167-gjp4-hpelitebook8570p-freebsd:~ #