Servidores DNS Principal (mname) y Secundario (rname)
host: egerdau.com.ar
class: IN
ttl: 600
type: SOA
mname: ns.gerdau.com.br
rname: hostmaster.e-gerdau.com.br
serial: 2023071700
refresh: 14400
retry: 3600
expire: 2678400
minimum-ttl: 600