Question and response
Question
dig mx-2.msgfocus.com. NS
Answer
mx-2.msgfocus.com. 4 CNAME mx-1.msgfocus.com.
Authority
msgfocus.com. 807 SOA ns-172.awsdns-21.com. awsdns-hostmaster.amazon.com. 1 7200 900 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0