Does "@" in CNAME record not work?

[Joseph S D Yao]

On Fri, Jul 13, 2001 at 02:32:58AM +0000, Jim Lum wrote:
...
> Then, as I read the book, I ran across the section that I cited above,
> which I took (and which I guess I still take) to imply that, in a
> "correct" DBxxx.. file, you should TRY to avoid having names with the
> same IP address.  I've read those two paragraphs (bottom of pg. 64, top
> of pg. 65) over several times, and I THINK that's what it's trying to
> say?
...

Cricket has said what he meant.  That paragraph refers specifically to
finding THE canonical name, from a "use" name.  CNAMEs allow this, so
if for ANY reason you want a human - or a savvy program - to know the
actual machine name without doing a reverse DNS lookup, then IF YOU CAN
you should use a CNAME record.  That's Cricket's recommendation, and as
always a good one.  But don't extend its application universally.

Name servers and mail servers should always have A records instead of
CNAME records.  This overrides that recommendation.  But whenever you
have multiple A records for the same IP address, cross-reference them
in comments or in some other immediately-obvious way.

Any name that has other records IS a canonical name - you must use an A
record, and cannot use a CNAME record [to try to pretend that some
other name is the canonical name].

You should not try to chain CNAMEs too far.  In fact, many believe that
any chaining is too far.

Hope this helps.

-- 
Joe Yao				jsdy at cospo.osis.gov - Joseph S. D. Yao
OSIS Center Computer Support					EMT-B
-----------------------------------------------------------------------
This message is not an official statement of COSPO policies.