Return different DNS results depending on client

You're correct assuming that to serve different results based on the "asking" DNS client you have to create views. It's quite simple.

1. Create ACL's (optional - you can use IP ranges everywhere, using ACL's is just easier):

   acl "not_poisoned_clients" {
       192.168.1.99/32;   # Caching server
       10.10.10.0/24;     # Example "whitelisted" network
   };
   

   NOTE: we're NOT creating specific ACL for "everyone else".
   
   

2. Create views (at least two). First one will match "whitelisted" clients, other - everyone else:

   view "not_poisoned_clients" {
       match-clients { "not_poisoned_clients"; };
       recursion yes;
       zone "example.com" {
           type master;
           file "/etc/named/zones/db.example.com";
       };
   };
   
   view "everyone_else" {
       match-clients { any; };
       recursion no;
       zone "poisoned_example.com" {
           type master;
           file "/etc/named/zones/db.example.com.poisoned";
       };
   };
   

   Above examples are very basic, to learn more about possible options I strongly recommend zytrax.com DNS guide, for example you can learn about all possible statements allowed within a "view" clause here.
   
   

3. Advanced RPZ configuration examples:

   • RPZ configuration - especially: look at the response-policy statement, which you can use in your views.