myadmin1.interserver.net has no CNAME records.
Question and response
Question
dig myadmin1.interserver.net. NS
Answer
The response has no answer records.
Authority
interserver.net. 587 SOA ns100.interserver.net. dns.cloudflare.com. 2396758241 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0