ns1.central01.net has no CNAME records.
Question and response
Question
dig ns1.central01.net. NS
Answer
The response has no answer records.
Authority
central01.net. 2986 SOA ns1.central01.net. joaopaulo.central01.net. 2026010501 3600 900 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0