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

Servidores DNS Principal (mname) y Secundario (rname)
host: healthcareisgrowing.com
class: IN
ttl: 600
type: SOA
mname: hdns.centene.com
rname: dnsadmin.centene.com
serial: 2
refresh: 10800
retry: 3600
expire: 2419200
minimum-ttl: 900