custmx.cscdns.net has no NS records.
NS records for this zone are defined at cscdns.net.
NS records for this zone are defined at cscdns.net.
Question and response
Question
dig custmx.cscdns.net. NS
Answer
The response has no answer records.
Authority
cscdns.net. 14400 SOA udns1.cscdns.net. hostmaster.cscdns.net. 2007080920 28800 7200 604800 14400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0