Glossary
A Record
An A record is the DNS entry that maps a domain name to an IPv4 address, telling browsers exactly which server hosts the website.
An A record ("Address" record) is the DNS entry that maps a hostname to an ipv4 address. It is the most common record type and the foundation of pointing a domain at a server.
Example
example.com. 3600 IN A 93.184.216.34
- The name on the left is the host.
3600is thettlin seconds.- The value is the IPv4 address visitors are routed to.
Related records
- For IPv6 addresses you use an
aaaa-recordinstead. - To alias one name to another rather than to an IP, use a
cname-record.
Why it matters for hosting
When you move to a new host, updating the A record is usually the key step that redirects traffic to the new server's ip-address. The change becomes visible only after the previous ttl expires across caches, which is why a low TTL is recommended before a migration.
See also
AAAA Record
An AAAA record maps a domain name to an IPv6 address, the IPv6 equivalent of an A record used for modern internet addressing.
CNAME Record
A CNAME record is a DNS alias that points one hostname to another, so the target resolves the destination name instead of an IP address.
IPv4
IPv4 is the original 32-bit internet addressing scheme, written as four dotted numbers, now exhausted and supplemented by IPv6.
DNS (Domain Name System)
DNS is the internet phone book that translates human-readable domain names like example.com into the IP addresses computers use to connect.
TTL (Time To Live)
TTL is the number of seconds a DNS record may be cached before resolvers must fetch a fresh copy, controlling how fast changes propagate.