root@nsn7:~# zfs list -r nsn7/lxd/containers
NAME                                     USED  AVAIL  REFER  MOUNTPOINT
nsn7/lxd/containers                     2,95G   259G    19K  /nsn7/lxd/containers
nsn7/lxd/containers/lds-xenial          2,68G   259G  3,16G  /var/lib/lxd/containers/lds-xenial.zfs
nsn7/lxd/containers/maas-trusty          214M   259G   214M  /var/lib/lxd/containers/maas-trusty.zfs
nsn7/lxd/containers/maas-trusty-virbr1  57,0M   259G   570M  /var/lib/lxd/containers/maas-trusty-virbr1.zfs

zfs get all nsn7/lxd/containers/maas-trusty|grep mount
nsn7/lxd/containers/maas-trusty  mounted               yes                                      -
nsn7/lxd/containers/maas-trusty  mountpoint            /var/lib/lxd/containers/maas-trusty.zfs  local
nsn7/lxd/containers/maas-trusty  canmount              on                                       default