Registro DMARC
v=DMARC1; p=reject; rua=mailto:DMARC_Monitoring@Columbia.com

Registro IPv4
host: columbia.mx
class: IN
ttl: 21600
type: A
ip: 23.227.38.65

Servidores DNS Principal (mname) y Secundario (rname)
host: columbia.mx
class: IN
ttl: 21600
type: SOA
mname: pdns1.ultradns.net
rname: benjamin\.sanders.columbia.com
serial: 2020040624
refresh: 86400
retry: 86400
expire: 86400
minimum-ttl: 86400