henger.cn.		30 IN SOA . hostmaster.nameserver. (
				77         ; serial
				28800      ; refresh (8 hours)
				7200       ; retry (2 hours)
				604800     ; expire (1 week)
				5          ; minimum (5 seconds)
				)

Mail exchangers:
henger.cn.		5 IN MX	10 mx125.72dns.net.