ns-foo.linpro.net has no CNAME records.
Question and response
Question
dig ns-foo.linpro.net. NS
Answer
The response has no answer records.
Authority
linpro.net. 10056 SOA a.ns.linpro.net. hostmaster.redpill-linpro.com. 2025092900 10800 3600 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0