ns1-cub.ipv6.ucsd.edu has no NS records.
NS records for this zone are defined at ipv6.ucsd.edu.
NS records for this zone are defined at ipv6.ucsd.edu.
Question and response
Question
dig ns1-cub.ipv6.ucsd.edu. NS
Answer
The response has no answer records.
Authority
ipv6.ucsd.edu. 900 SOA act-vnios-2.ucsd.edu. hostmaster.ucsd.edu. 1447286451 10800 3600 2419200 900
Additional
. 0 OPT ; payload 1220, xrcode 0, version 0, flags 0