CNAME records are domain name aliases.
Often computers on the Internet have multiple functions such as web-server, ftp-server, chat-server etc.
To mask this, CNAME-records
can be used to give a single computer multiple names (aliases).
For example computer "www.mycomputer.com" may be both a web-server and an ftp-server, so two CNAME-records are defined:
"www.mycomputer.com" = "xyz.com" and "ftp.mycomputer.com" = "xyz.com".
Sometimes a single server computer hosts many different domain names such as web servers that host many sites. In this example many CNAME records may be defined such as "www.abc.com" = "www.xyz.com".
The most popular
use the CNAME-record type is to provide access to a web-server using both the
standard "www.domain.com" and "domain.com" (without the
This is usually done by creating an A-record for the short name (without www), and a CNAME-record for the www name pointing to the short name.
CNAME-records can also be used when a computer or service needs to be renamed, to temporarily allow access through both the old and new name.
A CNAME-record should always point to an A-record to avoid circular references.