# Set volmode=dev is preferred for iSCSI volumes
# create a zvol with compression on and checksum off. Dangerous
zfs create -V 10G -o volmode=dev -o checksum=off -o compression=on storage/virtual_1
# create a ZFS Volume named virtual_2 to be exported.
zfs create -V 10G -o volmode=dev storage/virtual_2
# zfs volumes are available under /dev/zvol
zfs list
ls /dev/zvol/storage