Which record specifies authoritative information about a DNS zone?

The Start of Authority (SOA) record serves a crucial role in DNS (Domain Name System) management as it contains authoritative information about a DNS zone. This record identifies the primary name server for the zone, provides a contact email for the administrator, and includes timing parameters that define how long DNS resolvers should cache the information before checking back for updates.

The SOA record establishes the official DNS server for the zone and provides the necessary data for other DNS records within that zone to be considered valid. It essentially defines the boundaries and control information for the DNS zone, ensuring that any queries for that domain are directed to the correct server and that the data retrieved is authoritative.

In contrast, other record types serve different purposes. For example, a CNAME (Canonical Name) record is used to alias one domain name to another, while the MX (Mail Exchanger) record specifies mail servers for handling email for the domain. A PTR (Pointer) record is typically used for reverse DNS lookups, translating an IP address back to a domain name. While all these records are important for different aspects of DNS functionality, the SOA record specifically defines the authority and administrative details of a DNS zone.