o20.ptr455.send.arlomail.net has no NS records.
NS records for this zone are defined at arlomail.net.
NS records for this zone are defined at arlomail.net.
Question and response
Question
dig o20.ptr455.send.arlomail.net. NS
Answer
The response has no answer records.
Authority
arlomail.net. 900 SOA ns-830.awsdns-39.net. awsdns-hostmaster.amazon.com. 1 7200 900 1209600 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0