$ORIGIN 20.30.10.in-addr.arpa.
$TTL 2d
@            SOA    ns.zold.and.   hostmaster.zold.and. (
             2017010600 3h 15m 1w 2d )
@            NS     ns.zold.and.
@            PTR    ns.zold.and.
3            PTR    ns.zold.and.
4            PTR    ns.zold.and.