mx.li-lu.ru has no CNAME records.
Question and response
Question
dig mx.li-lu.ru. NS
Answer
The response has no answer records.
Authority
li-lu.ru. 215 SOA ns3-l2.nic.ru. postmaster.li-lu.ru. 65012925 14400 3600 2592000 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0