Registro DMARC
v=DMARC1; p=reject; rua=mailto:a@dmarcreports.facebook.com;

Servidores DNS Principal (mname) y Secundario (rname)
host: 2-ee.com
class: IN
ttl: 1241
type: SOA
mname: a.ns.facebook.com
rname: dns.facebook.com
serial: 4207849484
refresh: 14400
retry: 1800
expire: 604800
minimum-ttl: 3600

Información TXT
host: 2-ee.com
class: IN
ttl: 4842
type: TXT
txt: v=spf1 -all
entries: Array