On Thu, 5 Mar 2015, Rudy Gevaert wrote: > Hello, > > I'm hitting a strange issue. A user had his mailbox grow (multiple > GB) without him noticing. > > I can clean up with cyr_expire. > > Multiple messages are actually the same. It seems that the client > uploads the message and deletes it immediately. > > Yesterday it filled up a partition, so I couldn't enable telemetry on > his mailbox to actually see what happened. > > The client is outlook 2013. > > Has anybody seen this issue before? I'm running 2.4.17 Yes, this is the same issue that I descriped in the attached message to info-cyrus last April. At one point we were seeing numerous instances of this every week, to the point that it was a potential denial of service attack against our mail system. Dozens of separate cases. Fortunately things seem to have settled down in the last 6 months. Individual Outlook clients can be fixed using the procedure described at: http://www.ucs.cam.ac.uk/email/hints-and-tips/hermes/outlook-ost The problem appears to be associated with virus scanner plugins to Outlook (at least AVG and Kaspersky: it is possible others are also affected). Applying the most recent patches to Outlook doesn't seem to help. So far the only way that I have been able to reproduce the precise effect including a tight spin of uploads and deletes was when I switched from one AV plugin to another. One of the people affected who I contacted reported that they had made a similar change directly before problems started. A Google search on "Outlook 2013 IMAP bandwidth problems" strongly suggested that the problem wasn't specific to our mail system, e.g: http://ddkonline.blogspot.co.uk/2013/06/outlook-2013-bug-when-using-imap-beware.html -- David Carter Email: David.Carter@xxxxxxxxxxxxx University of Cambridge, Phone: (01223) 334502 Information Services, Fax: (01223) 334679 7 J J Thomson Avenue, Cambridge UK. CB3 0RB >From dpc22@xxxxxxxxx Tue Apr 29 13:00:27 2014 Date: Tue, 29 Apr 2014 12:56:07 +0100 From: David Carter <dpc22@xxxxxxxxx> To: info-cyrus@xxxxxxxxxxxxxxxxxxxx Subject: Outlook 2013 broken synchronisation We have had a couple of cases recently where the IMAP synchronisation process in Outlook 2013 seems to go nuts. The client system APPENDs large numbers of messages stored on the user's local hard disk to the Cyrus inbox and then deletes and expunges them (one at a time). It does this repeatedly. "X-OlkEid:" in the message headers and MIME multipart boundary markers in the body are different in each message, so the additional messages aren't exact copies. (I guess this could be some kind of broken filter rule. At the moment I'm working with third hand information). In one case the client managed to generate a 3.5 GByte cyrus.cache file (with about 1.5 million recently expunged messages), which is dangerously close to the 4 GByte limit on that file. We are running Cyrus 2.4.17. I appreciate that this isn't really a Cyrus question: I was just hoping that someone somewhere had seen the same effect and had worked out how to make Outlook behave. A Google search suggests that Microsoft "improved" the IMAP support in Outlook 2013, but I haven't found a specific match to the symptoms that I am seeing. -- David Carter Email: David.Carter@xxxxxxxxxxxxx University of Cambridge, Phone: (01223) 334502 Information Services, Fax: (01223) 334679 7 J J Thomson Avenue, Cambridge UK. CB3 0RB ---- Cyrus Home Page: http://www.cyrusimap.org/ List Archives/Info: http://lists.andrew.cmu.edu/pipermail/info-cyrus/ To Unsubscribe: https://lists.andrew.cmu.edu/mailman/listinfo/info-cyrus ---- Cyrus Home Page: http://www.cyrusimap.org/ List Archives/Info: http://lists.andrew.cmu.edu/pipermail/info-cyrus/ To Unsubscribe: https://lists.andrew.cmu.edu/mailman/listinfo/info-cyrus
