Registro IPv4
host: 51n.net
class: IN
ttl: 120
type: A
ip: 74.121.191.90

Servidores DNS Principal (mname) y Secundario (rname)
host: 51n.net
class: IN
ttl: 600
type: SOA
mname: dns.bizcn.com
rname: abuse.bizcn.com
serial: 8
refresh: 28800
retry: 14400
expire: 14400
minimum-ttl: 600