Servidores DNS Principal (mname) y Secundario (rname)
host: smtcdns.net
class: IN
ttl: 300
type: SOA
mname: ns1.smtcdns.net
rname: webmaster.smtcdns.net
serial: 1341562830
refresh: 300
retry: 600
expire: 86400
minimum-ttl: 300