Registro DMARC
v=DMARC1; p=reject; rua=mailto:dmarc@numerosgratuitos.info; ruf=mailto:dmarc-forensics@numerosgratuitos.info; fo=1; pct=100; ri=86400

Servidores DNS Principal (mname) y Secundario (rname)
host: numerosgratuitos.info
class: IN
ttl: 3600
type: SOA
mname: ns1-01.azure-dns.com
rname: azuredns-hostmaster.microsoft.com
serial: 1
refresh: 3600
retry: 300
expire: 2419200
minimum-ttl: 300