nic.ping	IN	NS	ns1.dns.nic.ping
nic.ping	IN	NS	ns2.dns.nic.ping
nic.ping	IN	NS	ns3.dns.nic.ping
nic.ping	IN	NS	ns4.dns.nic.ping
nic.ping	IN	NS	ns5.dns.nic.ping
nic.ping	IN	NS	ns6.dns.nic.ping