mail2.telecentro.com.ar has no CNAME records.
Question and response
Question
dig mail2.telecentro.com.ar. NS
Answer
The response has no answer records.
Authority
telecentro.com.ar. 1800 SOA ns1.telecentro.net.ar. webmaster.telecentro.com.ar. 2026022602 7200 3600 3600000 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0