Servidores DNS Principal (mname) y Secundario (rname)
host: hostpro.es
class: IN
ttl: 90
type: SOA
mname: ns1.dondominio.com
rname: dnsadmin.dondominio.com
serial: 2026052601
refresh: 10800
retry: 1800
expire: 691200
minimum-ttl: 3600