A, AAAA and CNAME Records Explained

A, AAAA and CNAME Records Explained

When you look inside a domain's DNS settings you will see several record types, each with a specific job. Three of the most common control where a name points: A, AAAA and CNAME records.

Knowing what each does makes it far easier to understand the instructions we send you and to spot when something has been set up incorrectly.

The Three Pointing Records

All three answer the question “where should this name go?”, but they answer it in different ways.

When Each Is Used

In practice you mix these records depending on whether you are pointing at a fixed address or at another name.

  • Use an A record to point a name at a specific IPv4 server address.
  • Use an AAAA record for the same purpose with a modern IPv6 address.
  • Use a CNAME to make one name an alias of another, inheriting its address automatically.
RecordPoints toTypical use
AAn IPv4 addressRoot domain to a server
AAAAAn IPv6 addressSame as A, for IPv6
CNAMEAnother domain nameSubdomain aliased to a service

Frequently Asked Questions

Can I use a CNAME on my root domain?

Traditionally no — the root usually needs an A record. Some providers offer ALIAS or flattened records to work around this.

If you need a hand with any of this, your Progressive Robot delivery team is ready to help. Raise a ticket from the Support area of your client portal or speak to your account manager and we will guide you through the next steps.

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