A Record
DNS record that maps a domain name to an IPv4 address.
An A-record is a DNS record that maps a domain name to an IPv4 address. When a client needs to reach example.com, the resolver queries the A-record and gets back an address such as 192.0.2.1 to connect to.
Every A-record carries a TTL (Time To Live) that controls how long resolvers and operating systems may cache the answer before querying again. A low TTL allows faster changes, a high TTL reduces DNS traffic.
A single domain can publish multiple A-records at the same time. DNS servers typically return them in rotating order (round-robin), which provides simple load balancing and redundancy across several IPv4 endpoints.
An A-record differs from an AAAA-record in that A points to IPv4 (32-bit) while AAAA points to IPv6 (128-bit). In dual-stack deployments both are published in parallel so clients can choose the protocol that their network actually supports.
Key Points
- Maps a domain name to one
IPv4address - Resolved through DNS by clients and resolvers
- Example:
example.com → 192.0.2.1 - TTL controls how long the answer is cached
- Multiple A-records enable round-robin and redundancy
- Differs from
AAAA-record, which points to IPv6