Registro DMARC
v=spf1 -all

Registro IPv4
host: medicaltextbook.com
class: IN
ttl: 1064
type: A
ip: 76.223.54.146

Registro IPv4
host: medicaltextbook.com
class: IN
ttl: 1064
type: A
ip: 13.248.169.48

Servidores DNS Principal (mname) y Secundario (rname)
host: medicaltextbook.com
class: IN
ttl: 1064
type: SOA
mname: ns2.afternic.com
rname: dns.jomax.net
serial: 1
refresh: 28800
retry: 7200
expire: 604800
minimum-ttl: 86400

Servidor de Correo
host: medicaltextbook.com
class: IN
ttl: 1064
type: MX
pri: 0
target: 

Información TXT
host: medicaltextbook.com
class: IN
ttl: 1064
type: TXT
txt: v=spf1 -all
entries: Array