$TTL 2d
.    IN   SOA   ns.root. hostmaster.ns.root. (
                      2         ; Serial
                 604800         ; Refresh
                  86400         ; Retry
                2419200         ; Expire
                 604800 )       ; Nagative Cache TTL
         
.         NS   ns.root.
ns.root.  A    10.30.20.1

$ORIGIN and.
@         NS   a.and.
a.and.    A    10.30.20.2