mx4.morganstanley.com has no NS records.
NS records for this zone are defined at morganstanley.com.
NS records for this zone are defined at morganstanley.com.
Question and response
Question
dig mx4.morganstanley.com. NS
Answer
The response has no answer records.
Authority
morganstanley.com. 3600 SOA ext-ns1.morganstanley.net. postmaster.ms.com. 39826 10800 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0