Servidores DNS Principal (mname) y Secundario (rname)
host: symcb.com
class: IN
ttl: 21600
type: SOA
mname: ns20.digicertdns.com
rname: dns.digicertdns.com
serial: 2009010209
refresh: 43200
retry: 3600
expire: 1209600
minimum-ttl: 180

Información TXT
host: symcb.com
class: IN
ttl: 300
type: TXT
txt: v=spf1 -all
entries: Array