ns01.t.is has no CNAME records.
Question and response
Question
dig ns01.t.is. NS
Answer
The response has no answer records.
Authority
t.is. 1800 SOA ns01.t.is. hostmaster.skyggnir.is. 2025101301 28800 7200 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0