Question and response
Question
dig smtp.itcom.info. NS
Answer
smtp.itcom.info. 5 CNAME mail.itcom.info.
Authority
itcom.info. 3471 SOA isp.24hc.ru. info.itcom.info. 2017052294 3600 3600 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0