mx.doubletreeclubohare.com has no NS records.
NS records for this zone are defined at doubletreeclubohare.com.
NS records for this zone are defined at doubletreeclubohare.com.
Question and response
Question
dig mx.doubletreeclubohare.com. NS
Answer
The response has no answer records.
Authority
doubletreeclubohare.com. 3600 SOA dns.doubletreeclubohare.com. hostmaster.doubletreeclubohare.com. 1753603083 43200 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0