[dns-operations] Why are cnames called "canonical" names?

Roland Dobbins rdobbins at arbor.net
Fri Apr 10 04:05:19 UTC 2015

On 10 Apr 2015, at 10:42, Mark E. Jeftovic wrote:

> Thanks to all who chimed in, I also understand what Evan meant when it 
> pointed out the distinction of what calling it "ALIAS" would have 
> meant.

from RFC2181:

10.1.1. CNAME terminology

    It has been traditional to refer to the label of a CNAME record as 
    CNAME".  This is unfortunate, as "CNAME" is an abbreviation of
    "canonical name", and the label of a CNAME record is most certainly
    not a canonical name.  It is, however, an entrenched usage.  Care
    must therefore be taken to be very clear whether the label, or the
    value (the canonical name) of a CNAME resource record is intended.
    In this document, the label of a CNAME resource record will always 
    referred to as an alias.

Roland Dobbins <rdobbins at arbor.net>

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