Which name server is used when a zone has no zone information but can answer with cached data?

Which name server is used when a zone has no zone information but can answer with cached data?

• A. Primary
• B. Secondary
• C. Authoritative
• D. Cache-only

Answer: (D)

The concept here is how DNS servers handle data and responses. A server that has no zone information but can answer using data it has previously cached is functioning as a cache-only name server. It doesn’t hold any authoritative copy of the zone’s records, but it can respond to queries with cached results until those entries expire (TTL). This is different from primary (master) or secondary (slave) servers, which actually store and serve the zone’s data authoritatively. It’s also not a typical authoritative server, since it has no zone data to answer authoritatively. So the described server best fits a cache-only name server.

The concept here is how DNS servers handle data and responses. A server that has no zone information but can answer using data it has previously cached is functioning as a cache-only name server. It doesn’t hold any authoritative copy of the zone’s records, but it can respond to queries with cached results until those entries expire (TTL). This is different from primary (master) or secondary (slave) servers, which actually store and serve the zone’s data authoritatively. It’s also not a typical authoritative server, since it has no zone data to answer authoritatively. So the described server best fits a cache-only name server.