smtpgw.itpartner.no has no CNAME records.
Question and response
Question
dig smtpgw.itpartner.no. NS
Answer
The response has no answer records.
Authority
itpartner.no. 600 SOA ns01.no.brand.one.com. hostmaster.no.brand.one.com. 2026030601 14400 3600 1209600 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0