configuring for EMSTP vs. SMTP mail for firewall

ams

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Jul 31, 1997, 3:00:00 AM7/31/97

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Please Help,

We're trying to configure the AltaVista Firewall 97 for DUNIX that is
using the MS Exchange Mail Server 5.0. Mail works internal addressing, we
can also get incoming mail to be delieved through the firewall.

Here's the problems;
We cannot send mail out the firewall. It appears the MS Exchange Mail
Server supports Extended SMTP Mail (EHLO) by default and the firewall
supports just SMTP (HELO).

when a User attemps to send a message to an external address the Exchange
Mail Server sends an EHLO message to the firewall which rejects it. The MS
Exchange Mail Server is suppose to come back and send a HELO message. It
appears to ONLY
function in an ESMTP mode.
We cannot see how to modify this via the GUI (MS Exchange). We check the
Registry and couldn't see any parameters associated with this either.

Here's what we have setup in the Exchange Mail Server:
Type Address Cost
Smtp * 1
Smtp 1

The tracking log and firewall mail.log indicate that an outgoing message is
being sent with the following sytnax:

to=bill+2EKam+40altavista+2Edigital+2Ecom+40fortressi+40companyA+2Ecom

Normal incoming messages have the following sysntax as expected:
from:kxxx...@altavista.digital.com
to:us...@companya.com

Any ideas would be appreciated.

Anthony

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Aug 1, 1997, 3:00:00 AM8/1/97

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Your firewall is parsing each and every message that passes through it?
Must be a lot of overhead.

ESMTP uses the same well-known port as SMTP (25). A firewall that passes
traffic for one presumably would pass traffic for the other.

EHLO is the standard way of identifying an ESMTP server. An ESMTP server
will respond with a list of the extended commands it supports; an SMTP
server will simply respond with an error message. Exchange uses EHLO as
the default because that's how ESMTP servers are supposed to work.

Note also that some mailers will reject a EHLO or HELO if the domain
specified in the command cannot be verified by a reverse lookup. This may
be what is happening to you, if you are getting a rejection from the remote
host. In that case you have to fix your DNS so that a reverse lookup
works.

I do not know of a way to change this behavior in Exchange. You would be
better off fixing your firewall (if the firewall is indeed at fault here).
--
Anthony

ams <b...@advmkt.com> wrote in article <01bc9e3a$7f144d60$1e010a0a@wks>...

Richard Ward

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Aug 2, 1997, 3:00:00 AM8/2/97

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I believe SP1 for Exchange 5.0 eliviates this problem.

RPW
___________

Rui M G Augusto

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Aug 14, 1997, 3:00:00 AM8/14/97

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My SMTP connection was working fine until I installed the SP1 for
Exchange 5.0. Since then, the SMTP/MIME Notes connector receives the
message fine but when it is processing the address it reads an address
of the type:

bill+2EKam+40altavista+2Edigital+2Ecom+40fortressi+40companyA+2Ecom

and the message is returned.
Do anyone know whot to put it to work just how it was working before?
any change in the registry?

thanks
Rui Augusto

> ----------
> From: r...@remote-axis.com (Richard
> Ward)[SMTP:r...@remote-axis.com]
> Posted At: Saturday, August 02, 1997 3:17 PM
> Posted To: exchange.admin
> Conversation: configuring for EMSTP vs. SMTP mail for firewall
> Subject: Re: configuring for EMSTP vs. SMTP mail for firewall