Eric,
When the connection is made, the receiving server says that it only
accepts messages up to 20,971,520 bytes. IMail should see the ESMTP
SIZE restriction and then not send the E-mail ( 41,874,785 bytes) and
create a bounce back to the sender. Is that not correct?
20050810 121147 127.0.0.1 SMTP (2725dc7000feb357) 250-SIZE
20971520
I don't yet know what the other server did according to it's own logs,
but I have seen 552 errors repeatedly ignored by all sorts of servers
when they are returned during a DATA transfer, thus causing similar
redelivery loops of very large messages. My logging on the other
server didn't give this level of detail, but I have increased it and I
can surely test it out (and I intend to do so). My point was however
that using EHLO should have prevented this situation from happening in
the first place.
Thanks,
Matt
Eric Shanbrom wrote:
The way I see the log is the
receiving server is not letting IMail know the message is too big. It
should send a 552 error code rather then just drop the connection. By
just dropping the connection IMail will look at it as a broken
connection and requeue the message... So in a nutshell, it looks like
the receiving server is broken
Eric S
-----
Original Message -----
Sent:
Thursday, August 11, 2005 4:33 PM
Subject:
[IMail Forum] IMail ignores EHLO message size limits??? Bad...
While looking into why my outbound bandwidth was spiking every 15
minutes I found that there was a 40 MB message in the spool that was
responsible for this. It was being resent every 15 minutes and taking
up gobs of bandwidth.
The server that it was sending to supports EHLO, in fact it is also my
own server. Here's what the session states after an EHLO command:
EHLO mail.mailpure.com
250-heimdall Hello [66.109.52.12]
250-SIZE 20971520
250-AUTH LOGIN CRAM-MD5
250 OK
My understanding of ESMTP is that if the message is more than
20,971,520 bytes as indicated in the SIZE response, then it should not
be sent. This message was more than 41,874,785 bytes and it was sent
regardless. Not such a big deal on it's own, but IMail never figures
out that the message is oversized even after sending it, and it
therefore just requeues the message and tries sending it until your
server's retry limit has been reached. I had also verified the same
thing a few weeks ago with yet another server (running MS SMTP) where
IMail would use EHLO but ignore the size limit and send regardless.
Here's the IMail log snippet.
20050810 121146 127.0.0.1 SMTP (2725dc7000feb357)
processing F:\\Q2725dc7000feb357.SMD
20050810 121146 127.0.0.1 SMTP (2725dc7000feb357) Trying
recip.example.com (0)
20050810 121146 127.0.0.1 SMTP (2725dc7000feb357) Connect
recip.example.com [66.109.52.200:25] (1)
20050810 121146 127.0.0.1 SMTP (2725dc7000feb357) 220
mail.mailpure.com
20050810 121146 127.0.0.1 SMTP (2725dc7000feb357) >EHLO
mail.mailpure.com
20050810 121147 127.0.0.1 SMTP (2725dc7000feb357) 250-heimdall
Hello [66.109.52.12]
20050810 121147 127.0.0.1 SMTP (2725dc7000feb357) 250-SIZE
20971520
20050810 121147 127.0.0.1 SMTP (2725dc7000feb357) 250-AUTH LOGIN
CRAM-MD5
20050810 121147 127.0.0.1 SMTP (2725dc7000feb357) 250 OK
20050810 121147 127.0.0.1 SMTP (2725dc7000feb357) >MAIL FROM:<[EMAIL PROTECTED]>
20050810 121147 127.0.0.1 SMTP (2725dc7000feb357) 250 OK <[EMAIL PROTECTED]>
Sender ok
20050810 121147 127.0.0.1 SMTP (2725dc7000feb357) >RCPT To:<[EMAIL PROTECTED]>
20050810 121147 127.0.0.1 SMTP (2725dc7000feb357) 250 OK <[EMAIL PROTECTED]>
Recipient ok
20050810 121147 127.0.0.1 SMTP (2725dc7000feb357) >DATA
20050810 121147 127.0.0.1 SMTP (2725dc7000feb357) 354 Start mail
input; end with <CRLF>.<CRLF>
20050810 121156 127.0.0.1 SMTP (2725dc7000feb357) >.
20050810 121156 127.0.0.1 SMTP (2725dc7000feb357) rl-recv:
connection reset
20050810 121156 127.0.0.1 SMTP (2725dc7000feb357)
20050810 121156 127.0.0.1 SMTP (2725dc7000feb357)
SMTP_DELIV_FAILED
20050810 121156 127.0.0.1 SMTP (2725dc7000feb357) >QUIT
20050810 121156 127.0.0.1 SMTP (2725dc7000feb357) rl-recv:
connection reset
20050810 121156 127.0.0.1 SMTP (2725dc7000feb357)
20050810 121156 127.0.0.1 SMTP (2725dc7000feb357) requeuing
F:\\Q2725dc7000feb357.SMD R0 T1
20050810 121156 127.0.0.1 SMTP (2725dc7000feb357) finished
F:\\Q2725dc7000feb357.SMD status=3
So what is going on here? Is IMail broken?
This issue can cause major problems as MS SMTP (used by Exchange
servers) has an issue where it will return a 552 error in the middle of
the DATA command instead of waiting for it to finish the transmission,
and some server's don't know to listen for one in the middle of a
transfer. So if a server is going to send oversized messages, it can
cause big bandwidth problems when they are tried over and over again.
FYI, I am using 8.15 HF1 currently.
Matt
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