The cname_ops form allows manipulation of cnames (DNS aliases). COs
have access to only those cnames for which both the "name" and the
target_name are in domains in their management zones. When modifying
or renaming an existing cname, that applies to both the old and the
new values.
Note that a CNAME is an alias of another DNS name, here called the
target_name, not a direct pointer to the records (e.g. the IP
addresses) owned by that name. This is different from an "aname" (or
"duplicate address record"), in which an IP address with a different
canonical name is pointed to directly. Manipulation of anames is
restricted to CS registrars. A CNAME cannot co-exist with an MX record
for a mail domain of the same name, and the IP registration database
enforces this: this is one case when an aname may be necessary
instead.
When creating a cname, the name, target_name and purpose
must be specified, the other fields are optional. The purpose
is arbitrary text, but should indicate what the alias is needed
for, e.g. "web site for the XXX project".
To display an existing cname, fill in name and click "display". You
can then change any of the attributes, including target_name, and
then click "modify". Alternatively you can use the "destroy" or
"rename as" functions.
The target_name must be the name of a box, vbox, aname or
(exceptionally) another cname in the database, and the object pointed
to cannot be removed until the cname has been deleted or had its
target_name changed. Pointing one cname at another ("CNAME chaining")
is usually best avoided, but the database does not prevent it being
used when really necessary.