auth210.NS.UU.NET has no CNAME records.
Question and response
Question
dig auth210.NS.UU.NET. NS
Answer
The response has no answer records.
Authority
ns.uu.net. 266 SOA AUTH00.NS.UU.NET. hostmaster.UU.NET. 129 3600 900 604800 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0