Servidores DNS Principal (mname) y Secundario (rname)
host: htc.edu.hk
class: IN
ttl: 78675
type: SOA
mname: ns7.imsbiz.com
rname: dnsadmin.imsbiz.com
serial: 2021099001
refresh: 10800
retry: 3600
expire: 604800
minimum-ttl: 86400

Servidor de Correo
host: htc.edu.hk
class: IN
ttl: 78676
type: MX
pri: 10
target: htc-edu-hk.mail.hk.greenradar.com

Servidor de Correo
host: htc.edu.hk
class: IN
ttl: 78676
type: MX
pri: 20
target: htc-edu-hk.mail.dr.greenradar.com