Registro DMARC
v=DMARC1;p=reject;fo=1;rua=mailto:mkxlz6lr@ag.dmarcian.com;ruf=mailto:mkxlz6lr@fr.dmarcian.com

Servidores DNS Principal (mname) y Secundario (rname)
host: blackboardservices.biz
class: IN
ttl: 900
type: SOA
mname: ns-1198.awsdns-21.org
rname: awsdns-hostmaster.amazon.com
serial: 1
refresh: 7200
retry: 900
expire: 1209600
minimum-ttl: 86400

Información TXT
host: blackboardservices.biz
class: IN
ttl: 90
type: TXT
txt: v=spf1 -all
entries: Array