r630.mit.edu has no CNAME records.
Question and response
Question
dig r630.mit.edu. NS
Answer
The response has no answer records.
Authority
mit.edu. 1800 SOA use2.akam.net. network-request.mit.edu. 22505 900 900 3600000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0