avn.vn.			30 IN SOA ns-master.inet.vn. postmaster.inet.vn. (
				2015072800 ; serial
				10800      ; refresh (3 hours)
				3600       ; retry (1 hour)
				604800     ; expire (1 week)
				3600       ; minimum (1 hour)
				)

Name servers:
avn.vn.			30 IN NS ns1.inet.vn.
avn.vn.			30 IN NS ns2.inet.vn.