mail.maxnet.ua has no CNAME records.
Question and response
Question
dig mail.maxnet.ua. NS
Answer
The response has no answer records.
Authority
maxnet.ua. 10800 SOA ns.maxnet.ua. admin.maxnet.ua. 2006040546 28800 14400 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0