Overview#
DNS Resource Records are the basic information elements of the Domain Name System.Each DNS Resource Records has a type (name and number), an Expiration Date (time to live), a class, and type-specific data.
DNS Resource Records of the same type are described as a resource record set (RRset). The order of resource records in a set, which is returned by a DNS resolvers to an application, is undefined, but often servers implement round-robin ordering to achieve load balancing. The Domain Name System Security Extensions (DNSSEC), however, work on the complete set of resource record in canonical order.
Resource record (RR) fields
| Field | Description | Length (Octet) |
|---|---|---|
| NAME | Name of the node to which this record pertains | Variable |
| TYPE | DNS record type of RR in numeric form (e.g., 15 for MX RRs) | 2 |
| CLASS | Class code | 2 |
| TTL | Count of seconds that the RR stays valid (The maximum is 231−1, which is about 68 years) | 4 |
| RDLENGTH | Length of RDATA field | 2 |
| RDATA | Additional RR-specific data | Variable, as per RDLENGTH |
Category#
Domain Name System (DNS)More Information#
There might be more information for this subject on one of the following:- ARecord
- DNS Certification Authority Authorization
- DNS record type
- Domain Name System
- Domain-based Message Authentication, Reporting & Conformance
- DomainKeys Identified Mail
- RFC 6844
- RR
- Sender Policy Framework
- TLSA
- [#1] - Domain_Name_System#DNS_resource_records
- based on information obtained 2017-10-30-