smtp.xpd.se has no CNAME records.
Question and response
Question
dig smtp.xpd.se. NS
Answer
The response has no answer records.
Authority
xpd.se. 3600 SOA nx1.xpd.se. fredrik.xpd.se. 2026030702 86400 7200 1814400 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0