Registro DMARC
v=DMARC1; p=reject;

Servidores DNS Principal (mname) y Secundario (rname)
host: rtklinc.com
class: IN
ttl: 7200
type: SOA
mname: NS31.WORLDNIC.com
rname: namehost.WORLDNIC.com
serial: 123021717
refresh: 10800
retry: 3600
expire: 604800
minimum-ttl: 3600

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