limestone.cs.wisc.edu has no CNAME records.
Question and response
Question
dig limestone.cs.wisc.edu. NS
Answer
The response has no answer records.
Authority
cs.wisc.edu. 600 SOA adns1.doit.wisc.edu. hostmaster.cs.wisc.edu. 2026016264 7200 1800 3628800 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0