[ On Monday, June 30, 2003 at 13:30:59 (+0530), Suresh Ramasubramanian wrote: ]
> Subject: Re: Now well off-topic - was Re: [Exim] how to configure HELO/EHLO and DNS for multi-homed hosts
>
> Forget dyndns - Greg seems to require that helo == forward dns ==
> reverse DNS
If by "dyndns" you mean those people who use automated or semi-automated
means to point their server names at dynamically assigned addresses,
such as those obtained from dial-up access or from DHCP on so-called
"broadband" access, _and_ where the PTRs for those addresses are also
not adjusted to match at the same time, then yes, that's right:
"dyndns" if fundamentally flawed and will forever be limited to be used
only those who feel they have no other viable choice.
If someone can't use an ISP who will agree to either adjust their PTRs for
them, or who will delegate such responsibility to them or their agent, then
either they signed a contract they should not have signed, or they probably
should think a lot harder about just what they think they're trying to do
and what price they're willing to pay to do it "their way".
> That will, for starters, bounce mail from virtual hosted domains
Actually it almost never does. Virtually hosted e-mail domains
generally use very well configured mail servers. They do this by
pointing their MX records at these shared servers, and usually the mail
sent out by users of those domains is relayed via their access
provider's authorised SMTP relay. Remember there's not necessarily any
direct correspondence between the client-SMTP and the sender address,
nor is there any direct correspondence between the name the server-SMTP
gives in its 220 greeting and the domains it accepts for local delivery
or private relay.
Anyone trying to do virtual e-mail hosting with A records doesn't really
know what they're doing -- they only know enough to be dangerous and
what they are doing is foolish.
> - and
> from hosts that don't have control over their rDNS (try coming here to
> APNIC land and see how hard it is to get your ISP to delegate rDNS to you).
Seems like some APNIC users have managed to get their reverse DNS
working just fine, though there are some others who are completely
brain dead when it comes to configuring reverse DNS.
--
Greg A. Woods
+1 416 218-0098; <g.a.woods@???>; <woods@???>
Planix, Inc. <woods@???>; VE3TCP; Secrets of the Weird <woods@???>
