Blocking queries to & responses from a given NS

[J]

Ronan,

Thanks for the reply.  blackhole {} looks like a useful option.  It
looks like something that I'd also want to use if I wanted a NS that
accepted queries from our customer subnets (via "allow-query" and
"allow-recursion" but blocked everything else "blackhole {any;}.

While I was waiting for a reply I also continued my research and I
believe I found the config option I used to use.  "bogus"   I'm now
using the sample below:

//  ###  BOGUS Servers  ###
// NS1.ZT-444.COM
server 64.20.39.26 { bogus yes ; };
// NS2.ZT-444.COM
server 64.20.33.130 { bogus yes ; };
// NS3.ZT-444.COM
server 64.20.33.3 { bogus yes ; };

As time permits I'll continue adding NSs that from DNS for Phishing
sites.  Thanks for the info.

J