Registro DMARC
v=DMARC1; p=reject; rua=mailto:dmarc_rua@emaildefense.proofpoint.com; ruf=mailto:dmarc_ruf@emaildefense.proofpoint.com;adkim=s;aspf=s;fo=1

Servidores DNS Principal (mname) y Secundario (rname)
host: nationalgridcommunications.com
class: IN
ttl: 14400
type: SOA
mname: dns1.cscdns.net
rname: hostmaster.cscdns.net
serial: 2024050903
refresh: 28800
retry: 7200
expire: 604800
minimum-ttl: 14400

Información TXT
host: nationalgridcommunications.com
class: IN
ttl: 14400
type: TXT
txt: v=spf1 -all
entries: Array