Servidores DNS Principal (mname) y Secundario (rname)
host: siblogga.it
class: IN
ttl: 83234
type: SOA
mname: dns.comune.siena.it
rname: postmaster.comune.siena.it
serial: 2015112701
refresh: 7200
retry: 3600
expire: 7200
minimum-ttl: 1800