Registro DMARC
v=DMARC1; p=reject; sp=reject; aspf=s; pct=100

Servidores DNS Principal (mname) y Secundario (rname)
host: rtklinc.com
class: IN
ttl: 21600
type: SOA
mname: ns1.markmonitor.com
rname: hostmaster.markmonitor.com
serial: 2025030301
refresh: 7200
retry: 900
expire: 1209600
minimum-ttl: 172800

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