Registro DMARC
v=spf1 -all

Registro IPv4
host: mathcourse.net
class: IN
ttl: 3600
type: A
ip: 76.223.54.146

Registro IPv4
host: mathcourse.net
class: IN
ttl: 3600
type: A
ip: 13.248.169.48

Servidores DNS Principal (mname) y Secundario (rname)
host: mathcourse.net
class: IN
ttl: 3600
type: SOA
mname: ns1.namefind.com
rname: dns.jomax.net
serial: 2023031500
refresh: 28800
retry: 7200
expire: 604800
minimum-ttl: 300

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