In which DNS zone would you store records that support reverse DNS lookups?

In which DNS zone would you store records that support reverse DNS lookups?

• A. Reverse lookup zone
• B. Forward lookup zone
• C. Primary zone
• D. Secondary zone

Answer: (A)

Reverse DNS lookups need a reverse lookup zone that holds PTR records mapping IP addresses back to hostnames. In DNS, forward lookup zones store mappings from names to addresses (A/AAAA records), while reverse lookup zones store the opposite: the PTR records that link an IP to its canonical name. For IPv4, the PTR records live in the in-addr.arpa namespace with the octets reversed; for IPv6, they live in the ip6.arpa namespace with the address nibbles reversed. The terms primary and secondary describe how zone data is stored and replicated, not the purpose of the zone. So, to support reverse lookups, you use the reverse lookup zone.

Reverse DNS lookups need a reverse lookup zone that holds PTR records mapping IP addresses back to hostnames. In DNS, forward lookup zones store mappings from names to addresses (A/AAAA records), while reverse lookup zones store the opposite: the PTR records that link an IP to its canonical name. For IPv4, the PTR records live in the in-addr.arpa namespace with the octets reversed; for IPv6, they live in the ip6.arpa namespace with the address nibbles reversed. The terms primary and secondary describe how zone data is stored and replicated, not the purpose of the zone. So, to support reverse lookups, you use the reverse lookup zone.