Re: DNS goofups galore...

[James Antill <james@and.org>]

"Henning P. Schmiedehausen" <hps@tanstaafl.de> writes:

> james@and.org (James Antill) writes:
> 
> >"Henning P. Schmiedehausen" <hps@tanstaafl.de> writes:
> 
> >> % telnet mail.bar.org smtp
> >> 220 mail.foo.org ESMTP ready
> >>     ^^^^^^^^^^^^
> >> 
> >> This kills loop detection. Yes, it is done this way =%-) and it breaks
> >> if done wrong.
> 
> > This is humour, yeh ?
> 
> No.

 This was a comment on the "loop detection" claim.

[snip ... domain example]

> No. This is a misconfiguration. Yes, RFC821 is a bit rusty but as far
> as I know, nothing has superseded it yet. And Section 3.7 states
> clearly:
> 
>       Whenever domain names are used in SMTP only the official names are
>       used, the use of nicknames or aliases is not allowed.

 _In_ SMTP, that doesn't say anything about MX records to me and even
if it does it's very old and needs to change.

> And the 220 Message is defined as
> 
> 220 <domain>

 So... you should have the reverse for the ip address after the
220. Which most people do (but not all, mainly due to there not being
enough ips).

[snip CNAME lesson]

 The question was, why can't you use CNAMEs. You said 'because of loop
detection'. I said 'But that doesn't work anyway, because you can have
to names pointing at one machine without a CNAME record ... and that
needs to, and currently does, work'.

> Dipl.-Inf. (Univ.) Henning P. Schmiedehausen       -- Geschaeftsfuehrer
> INTERMETA - Gesellschaft fuer Mehrwertdienste mbH     hps@intermeta.de

 Let me put it this way...

tanstaafl.de.		IN MX	50 mail.hometree.net.
tanstaafl.de.		IN MX	10 mail.intermeta.de.
intermeta.de.		IN MX	50 mail.hometree.net.
intermeta.de.		IN MX	10 mail.intermeta.de.

mail.hometree.net.	IN A	194.231.17.49
mail.intermeta.de.	IN A	212.34.181.3

49.17.231.194.in-addr.arpa.  IN PTR  limes.hometree.net.
3.181.34.212.in-addr.arpa.  IN PTR  babsi.intermeta.de.

-- 
# James Antill -- james@and.org
:0:
* ^From: .*james@and\.org
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