webmail-odc1.csgi.com has no CNAME records.
Question and response
Question
dig webmail-odc1.csgi.com. NS
Answer
The response has no answer records.
Authority
csgi.com. 11 SOA ns1.csgsystems.com. postmaster.csgsystems.com. 20112138 900 600 1209600 900
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0