Maybe I didn't express myself properly. Spamdyke was timeing out the
connection perfectly correctly because the client was inactive for more than
60 seconds which was spamdyke's default idle timeout. So the client's
Outlook sees the disconnection and retries, often resulting in another
partial copy of the same message. That is why I've probably fixed it by
setting "idle-timeout-secs=1200", which should handle even the slowest
clients.

But it's not the cause, it's the effect that concerns me. The partial
message received before the disconnection (e.g. 50 Kb of a 200Kb email) has
been piped to qmail-smtpd which then actually delivers it. How could
qmail-smtpd deliver a message that has not been properly terminated? Does
spamdyke simply close the pipe to qmail-smtpd, as would happen if
qmail-smtpd were connected directly to the client and qmail-smtpd initiated
the timeout?

Somehow a fundamental principle of SMTP MTAs is being breached, namely that
an incomplete session will never result in delivery, local or remote, of a
partial message.

My details:

xinetd.d
---------
server = /var/qmail/bin/tcp-env
server_args = -Rt0 /usr/local/bin/spamdyke -f
/usr/np/mail/spamdyke/spamdyke.conf /var/qmail/bin/qmail-smtpdauth
/var/qmail/bin/checkpassword /bin/true

Clamav and Spamassassin are only run after qmail-local pipes it to procmail
via the .qmail file, so they can't be affecting the issue. Of course neither
of those programs are run when the recipient is remote and qmail-remote
handles it. But even remote recipients are receiving multiple, partial
copies of the same message

Cheers and thanks for the response,
Chris Robinson

----- Original Message -----
From: "Sam Clippinger" <[EMAIL PROTECTED]>
To: "spamdyke users" <[email protected]>
Sent: Wednesday, February 06, 2008 18:11
Subject: Re: [spamdyke-users] Spamdyke passes partial emails to qmail after
timeout


> Most likely, this is a virus/spam filter issue.  Some qmail
> installations pass the incoming email to Spamassassin or ClamAV before
> acknowledging the delivery.  When that happens, spamdyke's idle timeout
> can trigger a disconnection if the scanner takes too long (this is
> common for large attachments).
>
> The best way to be sure is to enable full logging (with "full-log-dir")
> and examine the logs for disconnected deliveries.  The log will contain
> timestamps that will show long each response was delayed.
>
> Of course, it's also possible you've found a bug. :)  In that case, I'll
> need to find a way to reproduce it, so I may need you to (privately)
> send me a few full logs along with details of your spamdyke configuration.
>
> -- Sam Clippinger
>
> Chris Robinson wrote:
> > Hi Everyone,
> >
> > I run mail servers for about 30 companies (qmail /spamdyke 3.1.0 /
Fedora
> > 2.4.21) and started experiencing a problem whereby some users complained
> > that they could send an email and it was received by the recipient
corrupted
> > multiple times in varying sizes until eventually the final version would
> > arrive correct in full. To cut a long story short I eventually tracked
it
> > down from a string in a user's Outlook log "Talk faster next time". A
google
> > revealed all. It wasn't coming from qmail but from spamdyke, which
explained
> > why I couldn't grep it in the qmail source.
> >
> > I've probably fixed it by setting "idle-timeout-secs=1200". But what
worries
> > me is why the recipient got anything except the final good email. If
> > spamdyke issues that 421 error then breaks the connection, the user's
> > Outlook can justifiably assume that the email won't have been accepted
by
> > the server, nor sent to the  recipient. But what seems to happen is that
the
> > part that has been received down the pipe so far has been passed by
spamdyke
> > to qmail-smtpd which has passed it to qmail-queue and thence to the
local or
> > remote recipient. Surely no "250 OK 123 qp 456" has come out of qmail?
> >
> > Is this a spamdyke issue or a qmail issue?
> >
> > Cheers,
> > Chris Robinson
> >
> >
> >
> > _______________________________________________
> > spamdyke-users mailing list
> > [email protected]
> > http://www.spamdyke.org/mailman/listinfo/spamdyke-users
> _______________________________________________
> spamdyke-users mailing list
> [email protected]
> http://www.spamdyke.org/mailman/listinfo/spamdyke-users
>

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