server.rpc-extra.net has no NS records.
NS records for this zone are defined at rpc-extra.net.
NS records for this zone are defined at rpc-extra.net.
Question and response
Question
dig server.rpc-extra.net. NS
Answer
The response has no answer records.
Authority
rpc-extra.net. 86400 SOA server.rpc-extra.net. root.rpc-extra.net. 8 21600 3600 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0