:iscman:`named` can subscribe to up to 64 Response Policy Zones, each of which
encodes a separate policy rule set. Each rule is stored in a DNS resource
record set (RRset) within the RPZ, and consists of a **trigger** and an
-**action**. There are four types of triggers and four types of actions.
+**action**. There are five types of triggers and six types of actions.
A response policy rule in a DNS RPZ can be triggered as follows:
+- by the IP address of the client
- by the query name
- by an address which would be present in a truthful response
- by the name or address of an authoritative name server responsible for
- to synthesize a "domain does not exist" (NXDOMAIN) response
- to synthesize a "name exists but there are no records of the requested
type" (NODATA) response
+- to drop the response
+- to switch to TCP by sending a truncated UDP response that requires the
+ DNS client to try again with TCP
- to replace/override the response's data with specific data (provided
within the response policy zone)
- to exempt the response from further policy processing