CNAME records, also known as Alias records, point a hostname to another hostname or FQDN. They are called Alias records because they point to other records that have the mapping for that domain. When a name server looks up a domain and finds it is a CNAME record, it replaces the name with the canonical name (the target of the CNAME) and looks up the new name. In a sense, a CNAME lookup performs two queries to reach the final resolution.
CNAME records are commonly used to point multiple hostnames to a single location. This is useful when you have multiple records pointing to the same location (usually a web server at the root of a domain). If that location changes, all you have to do is change the endpoint in the record you’re pointing all those CNAME’s to. CNAME records can also be used to point a host name to a location that is external to the domain.
As per RFC 1035, CNAME records must be unique and cannot share the same FQDN/hostname with any other record in the managed domain.
1. Select your Domain
A. Select Managed DNS
B. Select Domains from the dropdown
C. Select the domain you want to add an CNAME record too.
2. Select CNAME Record
Under the CNAME records section, click the (+) icon to add a record.
3. Enter Record Values
A. Name: The hostname for the record. Note: CNAMEs cannot be set at the root (@) of a domain, we developed ANAME Records to fill this need.
B. TTL: Time to Live, measured in seconds, determines how long the record is cached in resolvers. For more information on best practices for TTLs, click here.
C. Record Mode: The Record Mode is how you enable settings like Failover, Record Pools, or Round Robin with Failover. You can read more about these settings here.
D. Geo Proximity: You can select a Geo Proximity rule to apply to the record, for more information on Geo Proximity, click here.
E. IP Filter: You can select an IP Filter to apply to the record, for more information on IP Filters, click here.
F. Disable Record: Information on the NX Domain feature can be found in the Disabling a Record tutorial.
G. Host: the fully qualified domain name you want to point to.
H. Notes: Add a helpful note with keywords so you can search for your records later.
I. Save and Close/Continue: Save and Close to finish entering A records or Save and Continue to add more records of the same type.