dns2.knology.net has no MX records.
Question and response
Question
dig dns2.knology.net. MX
Answer
The response has no answer records.
Authority
knology.net. 3600 SOA dns1.knology.net. npse-cloud-infrastructure-and-application-operations\@wowinc.com.knology.net. 2025081200 10800 3600 3600000 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0