The Kolab Now Staff is going to update parts of the platform to get rid of even more old infrastructure, and to ensure the best possible solution for users. Therefore we declare a service window on:
Friday 2023-06-09 at 08:00 UTC until 12:00 UTC.
Posts Tagged ‘IMAP’
Update on the ongoing performance issue
During the last 2 days Kolab Now has experienced a serious performance degradation issue. Users see that logins to- and operations in the webclient is taking a long time, and users connecting via desktop or mobile clients might not be able to perform synchronizations.
In the end of Wednesday it was thought that the root cause was found, and many users saw better performance for a while, but Thursday morning the performance dropped back to unacceptable levels.
Another iPhone ‘LIST-STATUS’ issue [FIXED]
In the beginning of the week we got a list of reports from users of iPhone connected via IMAP. These users reported that they were unable to list their mail folders. You can read about this issue in a previous blog post on this blog.
Outlook and return options to LSUB
A while back, users started to experience issues with IMAP LIST Extension for Special-Use Mailboxes. This to a level where a decision was made to temporarily suspend supporting Special-Use at Kolab Now.
Lately we have found ways to get around the problems that were present back then, and over the change of the year we introduced an update that, among other great improvements, contained these solutions and re-enabled the Special-Use.
Unfortunately, meanwhile Microsoft has also updated Outlook, and their update has changed the return options that Outlook is using with the LSUB command on the IMAP server.
This has caused issues for some users, who connect Outlook to Kolab Now via IMAP. Those users are suddenly not able to see some of their folders and mails in Outlook. The folders are perfectly visible in the web client and in other IMAP clients like mobile clients, Mac Mail and Thunderbird.
While the RFC compliance issue (the LSUB command does not accept a client specifying RETURN options) certainly has been made visible by Microsoft changing the behavior of Outlook, inversely Kolab Now providing an update to the benefit of all other clients has suddenly shown the related Outlook behavior to be faulty.
The root cause of the issue can be narrowed down to the expectations from Cyrus IMAP while parsing the LSUB command. Besides filing an upstream ticket, Kolab Systems has engaged in this issue and is contributing a fix to the Cyrus IMAP code. This fix is now going through test and QA, and should be ready to be deployed to Kolab Now soon.
If you are one of the users, who has problems because you are connecting Outlook to Kolab Now via IMAP, then you can work around the issue by – either using another IMAP client – or by connecting your Outlook to Kolab Now via ActiveSync, until the fix for Cyrus IMAP is ready and deployed.
If you have any questions or concerns in this context, then please contact support@kolabnow.com.
iOS IMAP Connection Issues Resolved
In the last few days, I’ve spent hours and hours configuring accounts on my private iPhone 6 running iOS 11 in order to attempt to nail down where its connection issues originate.
I’m happy to be able to tell you I seem to have nailed it down, and there’s a quick fix for it, that we can apply on the server-side.
Incident Report: Backend Down
Earlier this morning, at 04:38 UTC, one out of the twenty-two IMAP backends in production stopped serving its mail spool, showing Input/Output errors on its disk. Our Standard Operating Procedure is to examine log files, flush vm caches, stop the virtual machine, and start it back up again. This occurred at 05:48 UTC. The IMAP backend in question did not come back up cleanly.
