Registro DMARC
v=DMARC1; p=reject; sp=reject; adkim=s; aspf=s; fo=1

Servidores DNS Principal (mname) y Secundario (rname)
host: jeff.guru
class: IN
ttl: 1800
type: SOA
mname: dawn.ns.cloudflare.com
rname: dns.cloudflare.com
serial: 2415313005
refresh: 10000
retry: 2400
expire: 604800
minimum-ttl: 1800

Servidor de Correo
host: jeff.guru
class: IN
ttl: 3600
type: MX
pri: 0
target: 

Información TXT
host: jeff.guru
class: IN
ttl: 3600
type: TXT
txt: v=spf1 -all
entries: Array