DNS Resource Records (RRs) – are the basic elements used in Domain Name System (DNS) to represent data to be distributed by the DNS protocol. In the DNS protocol, Resource Records (RRs) are organized into zones based on the hostname that they are associated with. This hostname is also called the “owner hostname” and must be specified for all resource records.
Examples of DNS Resource Records (RRs) include:
“A” – ARecords are used in the DNS to define an IPv4 address binding for a hostname. For a given hostname, it is possible to have multiple ARecords if the hostname in question has multiple address bindings.
“AAAA” – IPv6 address record, Returns a 128-bit IPv6 address, most commonly used to map hostnames to an IPv6 address of the host.
“CNAME” – Canonical Name Record. Alias of one name to another: the DNS lookup will continue by retrying the lookup with the new name.
“MX” – Mail eXchange record. Maps a domain name to a list of message transfer agents for that domain.
“NAPTR” – Naming Authority Pointer. Allows regular-expression-based rewriting of domain names which can then be used as URIs, further domain names to lookups, etc.
“NS” – Name Server record. Delegates a DNS Zone to use the given authoritative name servers.
“SRV” – Service location record. Used for newer protocols instead of creating protocol-specific records such as MX.
