Servidores DNS Principal (mname) y Secundario (rname)
host: economia.unical.it
class: IN
ttl: 21600
type: SOA
mname: ccunt13.ccuc.unical.it
rname: apm.unical.it
serial: 2016062102
refresh: 86400
retry: 3600
expire: 604800
minimum-ttl: 86400