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

Servidores DNS Principal (mname) y Secundario (rname)
host: nexac.com
class: IN
ttl: 21600
type: SOA
mname: ns1.markmonitor.com
rname: hostmaster.markmonitor.com
serial: 2025062702
refresh: 86400
retry: 3600
expire: 2592000
minimum-ttl: 172800