Martin A. Brooks wrote:
> On 07/06/2009 16:04, W B Hacker wrote:
>> as a public-facing MTA really, really does need to have a fixed-IP
>> with a valid PTR RR
>
>
> It doesn't matter how many times you say this, it's simply not true. No
> RFC requires this.
That is a research shortfall - not lack of published information.
Start here:
http://en.wikipedia.org/wiki/Reverse_DNS_lookup
Be aware that smtp *relies on* 'many' other RFC's - it does not redefine them.
Ergo you have to look not only within the smtp-relevant RFC's (of which there
are several), but also at the RFC's for the infrastructure(s) they utilize.
> This is you saying "I think a public-facing MTA
> really, really does need to have a fixed-IP with a valid PTR RR".
Not *me*... you persist in shooting (at) (one of) the messengers.
But I couldn't have said it better than whomever cited the relevant RFC's on
Wikipedia:
/*
Internet standards documents (RFC 1033, RFC 1912 Section 2.1) specify that
"Every Internet-reachable host should have a name" and that such names are
matched with a reverse pointer record.
*/
That is not *limited* to smtp. Part of the reason you are not finding it.
But being able to 'vet' from whence and whom a connection is offered AND whether
at least an identifiable 'cousin' of that host might reasonably be expected to
be available to accept return traffic....
.. is certainly more crucial to keeping smtp 'sane' than whether a webserver or
ftp server has an assigned domain.tld and PTR RR.
> Please express such things as opinions, and not as universally accepted
> facts or technical requirements, which is what they, however
> unintentionally, come across as.
>
Because, dear hearts, 'technical requirements' is what they *ARE*!
I didn't *invent* them. I just read them.
Complied, advised others to do likewise.
Not everything in RFC's makes unconditional 'sense'. These DO. Bigtime.
smtp does not operate in a vacuum. It needs TCP/IP and BIND. Or equivalent.
RT-Mike-Foxtrot-RFC's All of those relevant.
Under a dozen in total IIRC, so it isn't all *that* onerous a task..
> And, yes, I know I'll get my usual bounce from your mail server when it
> throws away yet another perfectly legitimate non-spam email, because I
> dare to send email from my home ADSL connection, starting the email in
> RFC1918 space, with no matching reverse DNS.
>
>
'perfectly legitimate' and 'from home adsl connection'
- especially when coupled with 'dare to' ... implying you DO know better ..
... can be more succinctly expressed in one or two words.
Travel with companions of your own choosing, be they Zombots, spammers,
spam-engine advocates, feather-merchants, or 'Merchant Bankers'...
But expect to be branded as such whenever you stand up and make a public fuss to
try and *justify* that choice ... on clearly *mendacious* grounds.
Bill
