What is a CNAME record?

CNAME record – A Canonical Name record (abbreviated as CNAME record) is a type of resource record in the Domain Name System (DNS) used to specify that a domain name is an alias for another domain, the “canonical” domain.

All information, including subdomains, IP addresses, etc., are defined by the canonical domain.

To use CNAME records, select CNAME from the Add Record. Then enter the hostname you would like to alias from and the fully-qualified domain name you would like to alias to. You may also enter @ in the Alias for field to represent the domain itself.

For example, if the domain were example.com and you wanted www.exampledomainname.com to point to exampledomainname.com you could put www in the name field and @ in the alias for field.

Restrictions

A CNAME must have no other records of other types (MX, A, etc). This is very important especially with the @ record. If you specify a CNAME record type for the @ hostname, then email will not route properly for this domain name.
CNAME records that point to other CNAME records should be avoided. It is possible to create infinite loops and other error conditions.
Other DNS record types that point to other names, such as NS, MX, PTR, and SRV should never point to a CNAME.

Example CNAME record format: www CNAME www.exampledomainname.com