mailer1.ezyield.com has no NS records.
NS records for this zone are defined at ezyield.com.
NS records for this zone are defined at ezyield.com.
Question and response
Question
dig mailer1.ezyield.com. NS
Answer
The response has no answer records.
Authority
ezyield.com. 7200 SOA a2-66.akam.net. hostmaster.ezyield.com. 2015111227 10800 600 604800 7200
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0