rh4.exsbs.net has no CNAME records.
Question and response
Question
dig rh4.exsbs.net. NS
Answer
The response has no answer records.
Authority
exsbs.net. 10800 SOA ns1.exsbs.net. hostmaster.digitalagent.net. 2005060207 43200 43200 43200 43200
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0