sendmail to exchange: message is sent but times out anyway
alf
running sm 8.13 on a linux (CentOS 4) box.
Problem: when sending to an exchange server, the send transaction
times out just after the message is sent, like this (the example
belows takes upwards of ten minutes to complete):
===
<Y...@zz.biz>... Connecting to mail.zz.biz. via esmtp...
220 server.zz.zz.biz Microsoft ESMTP MAIL Service, Version:
6.0.3790.3959 ready at Thu, 15 Nov 2007 11:28:37 +0100
>>> EHLO storage.qq.es
250-SIZE
250-ETRN
250-DSN
250-ENHANCEDSTATUSCODES
250-8bitmime
250-AUTH GSSAPI NTLM LOGIN
250 OK
>>> MAIL From:<gfer...@rerere.it>
250 2.1.0 gfer...@rerere.it....Sender OK
>>> RCPT To:<Y...@zz.biz> NOTIFY=NEVER
250 2.1.5 Y...@zz.biz
>>> DATA
354 Start mail input; end with <CRLF>.<CRLF>
>>> .
<Y...@zz.biz>... Deferred: Connection timed out with mail.zz.biz.
Closing connection to mail.duerre.biz.
==
It would appear that exchange is waiting for something (line
terminator?) that sendmail never sends.
Whose fault is this? How do I get around it?
Cheers,
alf
Andrzej Adam Filip
Have you rule out MTU related problems?
http://www.sendmail.org/faq/section3.html#3.10
Have you tried to use tcpdump (or similar prohgram) to trace the TCP
session?
--
[pl>en: Andrew] Andrzej Adam Filip : an...@priv.onet.pl : an...@xl.wp.pl
Open-Sendmail: http://open-sendmail.sourceforge.net/
Bill Cole
<3bc262e3-fd37-4a18...@k62g2000hse.googlegroups.com>,
alf <alessandro...@gmail.com> wrote:
Wrong.
The '.' on a line by itself is the message terminator. After that, the
sending side is waiting for receiving side to respond.
> Whose fault is this?
Exchange or possibly something in between that is failing to transmit to
Exchange what sendmail is sending.
> How do I get around it?
Figure out why Exchange isn't sending any acknowledgment of the message.
In addition to some intermediary doing harm, another common problem is
filtering of mail done at that final point which is simply taking too
long.
--
Now where did I hide that website...
alf
On Nov 19, 2:51 am, Bill Cole <b...@scconsult.com> wrote:
[...]
> > It would appear that exchange is waiting for something (line
> > terminator?) that sendmail never sends.
>
> Wrong.
> The '.' on a line by itself is the message terminator. After that, the
> sending side is waiting for receiving side to respond.
I can see the dot... I was referring to something in the (harder to
spot) <CR><LF> sequnce that should follow it. Actually, for the
reasons that are explained in my other message above, "sendmail
never sends" is probably better worded as "the other end never
receives".
Cheers,
alf
alf
[...]
> Have you rule out MTU related problems?http://www.sendmail.org/faq/section3.html#3.10
>
> Have you tried to use tcpdump (or similar prohgram) to trace the TCP
> session?
>
Greetings.
A little more detail on my situation: I am at an ISP and the source
server handles several tens of thousands of messages per day, with few
problems if any. I noticed these problem situations just because the
messages accumulated in the queue waiting for "delivery" (which I am
speculating happened anyway after the connectiont timeout).
So I am pretty sure that the sendmail installation works most of the
time towards most servers (several of whom are certainly exchange). So
MTU cannot really be toyed with. I did not try tcpdump (I will) but I
expect to see that the <CR><LF>.<CR><LF> is correctly sent. If I were
to place a bet, I'd say some router/firewall is mangling the
connection (PIX have been known to do something very similar). But I
cannot rule out that the specific coupling of sendmail/exchange
version is causing the sanfu.
Cheers,
alf
Bill Cole
<5178cc0a-0f27-42b5...@41g2000hsh.googlegroups.com>,
alf <alessandro...@gmail.com> wrote:
Indeed.
The other end being a piece of software garbage from a developer with a
solid history of not understanding networking or SMTP, I suggest
approaching the problem from that end.
In general, I can testify to Sendmail talking to Exchange successfully
hundreds of thousands of times every day on machines I manage.
Peter Peters
>In general, I can testify to Sendmail talking to Exchange successfully
>hundreds of thousands of times every day on machines I manage.
I see the same. But sometimes the Exchange server (esp when there are
more than one) takes a long time to store the message. Enough to exceed
the timeouts.