Servidores DNS Principal (mname) y Secundario (rname)
host: pian-ku.com
class: IN
ttl: 1800
type: SOA
mname: launch1.spaceship.net
rname: support.spaceship.com
serial: 1777019216
refresh: 43200
retry: 3600
expire: 604800
minimum-ttl: 3600