$ORIGIN dyn.example.com.
$TTL 90 ; seconds
@	IN	SOA	ns1.example.com. hostmaster.example.com. (
                        2015122401      ; serial
                        1h              ; refresh
                        20m             ; retry
                        4d              ; expire
                        15m             ; nxdomain ttl
                        )
		NS	ns1.example.com.
		NS	ns2.example.com.
		TXT	"Dynamic Domain Example/Pinneberg, Germany"