Registro DMARC
v=DMARC1; p=reject; sp=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: medcorssucks.com
class: IN
ttl: 21600
type: SOA
mname: ns.cigna.com
rname: dnsdhcpipam.cigna.com
serial: 104
refresh: 10800
retry: 3600
expire: 2419200
minimum-ttl: 300

Información TXT
host: medcorssucks.com
class: IN
ttl: 21600
type: TXT
txt: v=spf1 -all
entries: Array