ns2.r01.RU has no MX records.
Question and response
Question
dig ns2.r01.RU. MX
Answer
The response has no answer records.
Authority
r01.RU. 600 SOA ns5.nic.RU. noc-dns.nic.RU. 2014080670 10800 1800 604800 600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0