Servidores DNS Principal (mname) y Secundario (rname)
host: windowswebspace.eu
class: IN
ttl: 3600
type: SOA
mname: dns2.a1.net
rname: domainadmin.a1.net
serial: 2019021300
refresh: 10800
retry: 3600
expire: 1814400
minimum-ttl: 3600