November 2023 - dovecot

doveadm sync - I/O has stalled
by songliny 09 Apr '24

09 Apr '24

Hi All, We are using dovecot 2.3.19.1 We created a account with more than 1000 mail folders in Maildir format to reproduce the issue. After weeks of testing, we have found a logic that may cause dsync to encounter the error - no activity for 900 seconds.... The function, dsync_ibc_stream_input, is the callback function after some data are ready for be read. This is part of what it does. o_stream_cork(ibc->output); ibc->ibc.io_callback(ibc->ibc.io_context); o_stream_uncork(ibc->output); Normally, ibc->ibc.io_callback(ibc->ibc.io_context) reads some data and then processes it. But when dsync connects over tcps, it uses function implementations in lib-ssl-iostream to send and receive data. And this simplified call stack would result in some data are read when calling o_stream_uncork o_stream_uncork => o_stream_flush => o_stream_ssl_flush_buffer => openssl_iostream_bio_sync => openssl_iostream_bio_input If some data arrive after ibc->ibc.io_callback(ibc->ibc.io_context) and before o_stre am_uncork, o_stream_uncork would read the data and then return. After o_stream_uncork returns, dsync then waits for new data to be read or written. But because the data had been read in o_stream_uncork, and there may be no new data to be read, dsync may then wait until timeout is met. It may happen, but it is hard to reproduce. If you also encounter this situation, you may try to use dsync over tcp connection. It does not read data when calling o_stream_uncork. As a result, it may not stuck. Back to the error itself, Maybe openssl-stream should not read data when doing uncork(flush)? Song-Lin Yang

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2.4 ballpark release date?
by Shawn Heisey 05 Apr '24

05 Apr '24

I'm wondering whether there is a ballpark release date for Dovecot 2.4. I know an exact release date is probably not available, but can it at least be narrowed to a specific quarter? Is it likely in 2023? I have seen on previous messages that an Ubuntu repository for 22.04 (jammy) will appear with the 2.4 release. My mail server in AWS is running Ubuntu 20.04 (focal), which I have avoided upgrading for various reasons, including websites that don't work with PHP 8.1. Now the last remaining hurdle is the fact that there is no dovecot repository for jammy. I would prefer the official Dovecot repo over dovecot packages included with Ubuntu, because it's likely to be a newer release, and built from vanilla project code. At the moment jammy includes dovecot 2.3.16, which is even older than the 2.3.20 that I am running on focal from the official dovecot repo. Again, I know that a precise release date won't be possible. I'm just hoping for something like "soon" or "in about six months." Thanks, Shawn

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[Dovecot] doveadm delete folders ?
by Robert Schetterer 19 Feb '24

19 Feb '24

Hi , is there a feature like doveadm expunge savedbefore ... for imap folder delete ? -- Best Regards MfG Robert Schetterer Germany/Munich/Bavaria

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Recommended changes for delivery from Exim
by jgh＠exim.org 05 Feb '24

05 Feb '24

Hi, Security changes to Exim have invalidated certain suggested configurations in the Dovecot wiki. As I do not have a Dovecot installation to test, I am not going to write any updates there. It would be good if someone would test these suggestions and then make updates as needed. 1) The use of $local_part and $domain in commands run by the "pipe" transport will be disallowed in the upcoming Exim release. These are currently noted as optional, with the "-m" flag to dovecot-lda. They should be replaced with validated (untainted) versions, commonly $local_part_data and $domain_data, developed via one of the several de-taint methods documented for Exim. The same applies to $original_local_part and $original_domain. 2) The use of $sender_address will likewise be disallowed. This and the "-f" flag can be dropped from the dovecot-lda command line, and the specification of a null "message_prefix" option removed. The defaults for a pipe transport will then prefix the message with a suitable Mbox "From " header line, which dovecot-lda is documented to extract the sender from. Both of these suggestions are back-compatible to the current 4.95 release of Exim, and will be required with the 4.96 release. -- Cheers, Jeremy Refs: - https://wiki.dovecot.org/LDA/Exim - https://doc.dovecot.org/configuration_manual/protocols/lda/

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JMAP support?
by Mark Constable 31 Jan '24

31 Jan '24

On Fri Jan 25 2019 Aki wrote: > There is no JMAP support in any dovecot version yet. Two years on so what is the status of JMAP support in Dovecot now?

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Replication going away?
by Vladimir Mishonov 26 Jan '24

26 Jan '24

Hello everyone. Just saw this commit in the official Github repo: https://github.com/dovecot/core/commit/4c04e4c30fd4817a8b0e11d04d9681173f69… Looking at the commit details, it appears that it completely removes the replication feature. I'm a bit perplexed by this change and am not sure what might be the justification for it. Personally, I find replication to be very useful, as it allows me to maintain a synchronized mirror of all of my mailboxes on my home server, for use as backup in case the primary server goes down for some reason. Perhaps there's some sort of replacement being planned for this feature? Or maybe the relevant code is simply going to be refactored to a plugin or external program, and there's nothing to worry about at all? In any case, I'd greatly appreciate if one of the developers could comment on this change. -- Kind regards, a concerned user of Dovecot (Vladimir)

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Forcing imap authentication failure for certain IP addresses
by Hippo Man 20 Jan '24

20 Jan '24

I'm running dovecot 2.3.18 under Debian 11. I want to do something that's a bit unusual: when IMAP connections are attempted from a few specific IP addresses, I want to force an IMAP authentication failure from those connections, no matter what user ID and password are specified. I know that I can use iptables to completely block imap access from those IP addresses to the IMAP ports. However, in these specific cases, I'd prefer that the connection goes through to dovecot, but for dovecot then to always generate authentication failures for those specific connections ... even if a valid user ID and password happen to be specified. Is there a way to do this in dovecot? Thank you very much in advance. -- hippoman(a)gmail.com Take a hippopotamus to lunch today. .---------, 0__0 / ( oo'---, / oo\ ,\ | | \ ,=__/ \ / / /------| /| |__|-' |__|'

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ARM support
by Brad Koehn 15 Jan '24

15 Jan '24

Hey there, I was wondering if you’re planning to support ARM in your packages and/or Docker images. Right now I’m stuck on whatever ships with Debian for ARM64 architectures. Otherwise, suggestions how would I go about building them myself? In a modern build world, it’s fairly straightforward, especially with Docker to handle all the emulation. Thanks for such a great product! I’ve used Dovecot on my little server for over twenty years. — Brad Koehn Hey there, I was wondering if you’re planning to support ARM in your packages and/or Docker images. Right now I’m stuck on whatever ships with Debian for ARM64 architectures. Otherwise, suggestions how would I go about building them myself? In a modern build world, it’s fairly straightforward, especially with Docker to handle all the emulation. Thanks for such a great product! I’ve used Dovecot on my little server for over twenty years. — Brad Koehn

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dovecot submission max line length
by Kees van Vloten 13 Dec '23

13 Dec '23

Hi all, After upgrading Debian Bullseye (Dovecot 2.3.13) to Bookworm (Dovcecot 2.3.19), submission-login returns an error on Kerberos authentication: "Client sent invalid command: Command line is too long". When I initially set this up on Bullseye I have seen the same issue, but adding "imap_max_line_length = 2M" solved it. Now with 2.3.19 kerberos authentication still works (with this setting) for imap connections but it stopped working for submission. Is there a new config setting for submission-login that I missed? Or is this a bug in 2.3.19? - Kees.

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replicator: Panic: data stack: Out of memory when allocating 268435496 bytes
by Gerben Wierda 06 Dec '23

06 Dec '23

One step further in my quest to create a replacement mail server. I now have my old mail server (2.3.19.1, macOS + MacPorts) and my new (2.3.20, Alpine Linux, Docker, apk package). When I turn on replication it works, but, after a while I see: Jan 06 00:50:31 replicator: Panic: data stack: Out of memory when allocating 268435496 bytes Jan 06 00:50:32 replicator: Fatal: master: service(replicator): child 133 killed with signal 6 (core dumped) Jan 06 00:50:32 lmtp(pid 195 user sysbh): Warning: replication(sysbh): Sync failure: Jan 06 00:50:32 lmtp(pid 195 user sysbh): Warning: replication(sysbh): Remote sent invalid input: - I've removed synchronous operation for now (found a message on the net suggesting that) but is this known and what does it mean? Gerben Wierda (LinkedIn <https://www.linkedin.com/in/gerbenwierda>) R&A IT Strategy <https://ea.rna.nl/> (main site) Book: Chess and the Art of Enterprise Architecture <https://ea.rna.nl/the-book/> Book: Mastering ArchiMate <https://ea.rna.nl/the-book-edition-iii/>

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