mailrelay2a.balt.net has no CNAME records.
Question and response
Question
dig mailrelay2a.balt.net. NS
Answer
The response has no answer records.
Authority
balt.net. 60 SOA dns1.balt.net. hostmaster.balt.net. 2012073740 3600 900 604800 60
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0