[exim] Problem - SMTP connector in Exchange 2003 sending mai…

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Συντάκτης: oll
Ημερομηνία:  
Προς: Richard.Hall
Υ/ο: exim-users
Αντικείμενο: [exim] Problem - SMTP connector in Exchange 2003 sending mail to Exim 4.43 - RESOLVED
Hi Richard and all,

This is what I did to resolve the issue.

Configured the dedicated SMTP connector in to not forward directly to the
Exim mail server anymore. I configured it to forward to a Barracuda mail
gateway box we have (www.barracudanetworks.com).

I then configured a smarthost on this box to forward mail to the Exim mail
server.

The mail conversion now happens on the Barracuda after being recieved from
Exchange and the Exim mail server recieves it fine.

Cheers,

/o


----- Original Message -----
From: "Richard.Hall" <Richard.Hall@???>
To: "oll" <o.moazzezi@???>
Cc: <exim-users@???>
Sent: Friday, April 08, 2005 10:59 PM
Subject: Re: [exim] Problem - SMTP connector in Exchange 2003 sending mail
to Exim 4.43


> Oll,
>
> On Fri, 8 Apr 2005, oll wrote:
>
> > Hi,
> >
> > Just subscribed to this list to see if any of you guys have ever
> > experienced this problem before?
>
> Been there, done that, haven't even had time to get the photos printed on
> the t-shirt yet ...
>
> > We have an SMTP connector in our Exchange 2003 org that will route out
> > mail that it does not find a recipient for for a certain domain. Let's
> > call it domain.com
>
> My problem was with an Exchange 2000 system, but I believe it's the same.
>
> > So if no one in our Active Directory has the email address
> > someone@??? it will route that mail out via this connector
> > directly to an Exim mail server. It is running Exim 4.43 (that's what
> > it says when I telnet to it).
> >
> >
> > Not all mail is getting to it, that is the problem.
> >
> > Some mails are returned stating:
> >
> > Action: failed
> > Status: 5.6.1
> > Diagnostic-Code: smtp;554 5.6.1 Body type not supported by Remote Host
>
> Yup, that's the one.
>
> > This only tends to happen when a mail is forwarded through the
> > connector when recieved by Exchange from certain web mail clients or
> > programs.
> >
> >
> > I've got a feeling this is a 7BIT/8BIT MIME problem
>
> Your diagnosis is spot on, I think.
>
> > so what I did on
> > the SMTP connector was disable ESMTP (effectively saying HELO instead
> > of EHLO) in the hope it would fix it and convert the mail correctly so
> > that the Exim 4.43 mail server could recieve the mail.
>
> No, you are tackling the problem too late :-(
>
> > However it still isn't..
> >
> > Again this is only happening with certain mails. It all depends what
> > format the message is recieved by Exchange it appears.
> >
> >
> > Anyone ever had this before? Is this a shortfall with Exchange or Exim
> > 4.43? Can it be fixed?
>
> Yes. The former (IMHO). Yes.
>
> This is (more or less) what I wrote at the time:-
>
> > Googling around for "Body type not supported by Remote Host" fairly
> > quickly leads to Microsoft KB 257569 at
> >
> >     http://support.microsoft.com/kb/257569

> >
> > entitled "How to turn off ESMTP verbs in Exchange 2000 Server and in
> > Exchange Server 2003"
> >
> > My understanding of what is happening is
> >
> > - remote sender connects to Exchange and sends EHLO
> > - Exchange responds, advertising various ESMTP extensions, and in
> > particular 8BITMIME
> > - the remote sender (probably another Exchange server) sends an

8-bit-mime
> > message to Exchange (The example I have is in German, with typical
> > German-accented 8-bit characters)
> > - Exchange connects to Exim and sends EHLO
> > - Exim responds but does _not_ advertise 8BITMIME. (It does not support

it
> > by default, and with good reason, as we are about to see)
> > - Exchange is _supposed_ to convert the 8-bit message into a suitable

7-bit
> > format. (I believe this is more than just a case of encoding 8-bit in
> > 7-bit, though I am very hazy on the details, and have not yet had time
> > to research it further.) However, it is unable to do so, so simply
> > bounces the message back to the sender.
> >
> > KB 262128 has a little more info on the subject. Also the following from
> > the Exim spec. may be useful:-
> >
> >                             ----- -----
> > Option: accept_8bitmime
> > Use:  main
> > Type:  boolean
> > Default:  false

> >
> > This option causes Exim to send 8BITMIME in its response to an SMTP EHLO
> > command, and to accept the BODY= parameter on MAIL commands. However,
> > though Exim is 8-bit clean, it is not a protocol converter, and it takes
> > no steps to do anything special with messages received by this route.
> > Consequently, this option is turned off by default.
> >                             ----- -----

> >
> > Clearly Exchange is also not capable of acting as a protocol converter;
> > yet it does advertise 8BITMIME by default.
>
> To summarise
>
> - once Exchange has accepted an 8BITMIME message, it is unable to pass it
> on to a (standard) Exim server.
>
> - so you have to prevent Exchange accepting it in the first place
>
> - which you do by preventing it advertising 8BITMIME in response to an
> EHLO from the remote sender.
>
> Caveat 1: this was so recent that I haven't yet had confirmation from the
> affected user that it actually works.
>
> Caveat 2: you are simply pushing the problem one step further back up the
> pipeline; if the original sender cannot send a non-8bitmime message in the
> first place, you are stymied.
>
> Caveat 3: Exchange also seems to advertise BINARYMIME; it may be that you
> need to disable that as well.
>
> HTH,
> Richard
>
>
>
>
>