[ILUG] ESMTP weirdness with one of {cisco|adsl}

[John Reilly]

try  "no fixup smtp" on the cisco.


----- Original Message -----
From: "Ronan Waide" <waider at waider.ie>
To: "ILUG main list" <ilug at linux.ie>
Sent: Friday, December 06, 2002 1:48 PM
Subject: [ILUG] ESMTP weirdness with one of {cisco|adsl}


> Hi folks,
>
> A little off-topic for ILUG, but.
>
> I'm digging into a problem here that's making no sense. I've got a
> mail server sitting behind a Cisco which talks to the rest of the
> world via an ADSL line provided by eircom. At present, if I try using
> EHLO to any server anywhere, I get a 502 response. This obviously
> means I can't go pick up mail from my secondary MXs, because no EHLO
> -> no ETRN.
>
> So.
>
> In pursuit of this problem, I've done a variety of tests and tcpdumps
> and ethereal traces and what not. Suffice to say it looks like
> something is filtering the SMTP channel, converting my outbound EHLO
> to NOOP, and converting the response (250) to 502.
>
> If I try another port, e.g. run up a sendmail server on port 4242 and
> EHLO to that, I get a 250 response like I'd expect. I'm pretty sure
> that all the Cisco is doing here is providing NAT services, since
> filtering EHLO seems to me like something you'd have to explicitly
> enable in the config somewhere.
>
> So. Am I to arrive at the conclusion that Eircom are messing with my
> EHLO stream, or is this some new Cisco feature I should be aware of?
> And if the latter, how do I turn the damn thing off?
>
> Cheers,
> Waider.
>
> ObLinux: I've been using a variety of Linux servers for my tracing :)
> --
> waider at waider.ie / Yes, it /is/ very personal of me.
>
> buzzard says, "If you are willing to put aside your kneejerk human
speciesism,
>     the AIs are perfectly sympathetically 'no worse' than humans."
<matrix>
> --
> Irish Linux Users' Group: ilug at linux.ie
> http://www.linux.ie/mailman/listinfo/ilug for (un)subscription
information.
> List maintainer: listmaster at linux.ie