Servidores DNS Principal (mname) y Secundario (rname)
host: jdsc.com.cn
class: IN
ttl: 235
type: SOA
mname: dns29.hichina.com
rname: hostmaster.hichina.com
serial: 2024042409
refresh: 3600
retry: 1200
expire: 86400
minimum-ttl: 600