mailslot.cs.purdue.edu has no CNAME records.
Question and response
Question
dig mailslot.cs.purdue.edu. NS
Answer
The response has no answer records.
Authority
cs.purdue.edu. 10800 SOA pendragon.cs.purdue.edu. postmaster.cs.purdue.edu. 2026030313 10800 3600 604800 10800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0