Hey, We have those exact same issues ever so often. They seem to happen at random but I figured out what was going wrong:
Our mail servers accepted the incoming connection and starting processing the mail with Spamassassin. Spamdyke keeps the connection open as long as Spamassassin does it's work in order to be able to give a negative feedback if the mail passes a certain threshhold in spam. Under normal cicrumstances this is not an issue. But sometimes mails are caught in the spamfilter for too long causing it to scan for longer than the default 60 seconds which most mail clients are setup to wait for a timeout. So what happens is that the remote client disconnects with a timeout while our servers are already processing the mail and eventually will deliver it to the mailbox. Sadly the connection is already gone so we can't tell the client that the message has been processed. They connect again after their timeout retry and the same thing happens again. The only way I was able to fix this was by including the IP of that sending host into our tcp file and excluding it from any scan mechanism until the message has been delivered. Otherwise the host would keep trying until it reaches a final timeout. This doesn't seem to be an issue with Spamdyke but rather Spamassassin taking way too long for a scan. Mails that are about 5kb in size should never take 120+ seconds for a scan ;) Hope this helps, Cheers, Sebastian On Fri, 2010-01-22 at 08:33 -0700, Eric Shubert wrote: > Hans F. Nordhaug wrote: > > Hi - I'm new to the list but I have searched ;-) > > > > We are running Spamdyke 4.0.10 (as included in Qmail Toaster Plus) > > with idle-timeout-secs set to 60. One of my users recently got 30 > > duplicate messages (and wasn't happy). Looking at the logs, I see that > > Spamdyke indeed timed out but the messages were (scanned by simscan and) > > delievered by Qmail to the user. How can this be? > > > > I understand that the sender's e-mail client (Outlook most likely, but > > I haven't checked) must have thought that the messages weren't > > delievered and hence retried. I first thought that this was a known > > bug in SpamDyke - see discussion in the "Spamdyke passes partial > > emails to qmail after timeout" thread: > > http://www.mail-archive.com/[email protected]/msg00744.html > > But this "bug" was fixed long time ago. What exactly does Spamdyke > > do when it timeouts? If the the client keeps the connection open long > > after completing the message transfer and spamdyke does X when timing > > out, could that confuse the client so it resends? > > > > Regards, > > Hans > > Hey Hans, > > Need a little more info to tell for sure what's happening, like whether > the messages was coming from an outside server, or from a local client. > > I'll go with your local client presumption, and also assume they're > using Outlook. When Outlook submits a message, it must wait for the > server to scan the message before the submission completes. If your > server is under a heavy load when a user submits a particularly large > email, this might take a couple minutes. The user doesn't notice this, > as Outlook is sending from its Outbox in the background. Outlook times > out after 1 minute by default, and if the server takes longer than that, > Outlook obligingly sends the message again a little later. To fix this > problem, increase Outlook's timeout setting. I do this on all Outlook > clients. FWIW I also configure them to use port 587, so spamdyke doesn't > come into play. ;) > > If this doesn't fix your problem, then I would guess that your server is > under heavy load at times and is taking a long time to scan messages. If > that's the case, you can remedy the situation by increasing the timeout > setting to 300 or so. A better solution though would be to speed up > scanning by putting the simscan working directory on a tmpfs (ram > drive). Jake has a howto video on this at > http://videos.qmailtoaster.com. I think that one's free, but I'm not sure. > > I expect that one or both of these solutions will solve your problem. > > P.S. If you're so inclined, please consider writing a FAQ about this on > the qmailtoaster wiki. ;) _______________________________________________ spamdyke-users mailing list [email protected] http://www.spamdyke.org/mailman/listinfo/spamdyke-users
