Servidores DNS Principal (mname) y Secundario (rname)
host: 51asr.com
class: IN
ttl: 180
type: SOA
mname: f1g1ns1.dnspod.net
rname: freednsadmin.dnspod.com
serial: 1724664605
refresh: 3600
retry: 180
expire: 1209600
minimum-ttl: 180

Servidor de Correo
host: 51asr.com
class: IN
ttl: 600
type: MX
pri: 5
target: stoffice.51asr.com