smtp1.integrys.it has no CNAME records.
Question and response
Question
dig smtp1.integrys.it. NS
Answer
The response has no answer records.
Authority
integrys.it. 730 SOA ns1.dns4userver.com. server.serverplan.com. 2025113006 10800 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0