Registro DMARC
v=DMARC1; p=none

Servidores DNS Principal (mname) y Secundario (rname)
host: jackshamburger.com
class: IN
ttl: 300
type: SOA
mname: ns1.systemdns.com
rname: hostmaster.systemdns.com
serial: 1752412777
refresh: 10800
retry: 3600
expire: 300
minimum-ttl: 60