Dovecot release v2.3.7

[Eirik Rye]

Version 2.3.7 appears to break director ring sync. After upgrading, our 
logs are full of these kinds of messages:

Jul 14 04:09:20 yyy dovecot: director: Error: director: User xxx host 
lookup failed: Timeout because ring not synced - queued for 30 secs 
(Ring not synced for 1410 secs, hash=271838221)
Jul 14 04:09:20 yyy dovecot: director: Error: director: User xxx host 
lookup failed: Timeout because ring not synced - queued for 30 secs 
(Ring not synced for 1410 secs, hash=3482757093)

As well as:

Jul 14 04:09:21 yyy dovecot: director: Error: Ring SYNC seq=53 appears 
to have got lost, resending

These are absent from the logs prior to July 12.

I have downgraded to 2.3.6 in hopes of resolving the issue.

Regards,
Eirik Rye

On 12/07/2019 14:29, Aki Tuomi via dovecot wrote:
> Hi!
> 
> We are pleased to release Dovecot release v2.3.7.
> 
> Tarball is available at
> 
> https://dovecot.org/releases/2.3/dovecot-2.3.7.tar.gz
> https://dovecot.org/releases/2.3/dovecot-2.3.7.tar.gz.sig
> 
> Binary packages are available at https://repo.dovecot.org/
> 
> Changes
> -------
> 
> * fts-solr: Removed break-imap-search parameter
> + Added more events for the new statistics, see
>    https://doc.dovecot.org/admin_manual/list_of_events/
> + mail-lua: Add IMAP metadata accessors, see
>    https://doc.dovecot.org/admin_manual/lua/
> + Add event exporters that allow exporting raw events to log files and
>    external systems, see
>    https://doc.dovecot.org/configuration_manual/event_export/
> + SNIPPET is now PREVIEW and size has been increased to 200 characters.
> + Add body option to fts_enforced. This triggers building FTS index only
>    on body search, and an error using FTS index fails the search rather
>    than reads through all the mails.
> - Submission/LMTP: Fixed crash when domain argument is invalid in a
>    second EHLO/LHLO command.
> - Copying/moving mails using Maildir format loses IMAP keywords in the
>    destination if the mail also has no system flags.
> - mail_attachment_detection_options=add-flags-on-save caused email body
>    to be unnecessarily opened when FETCHing mail headers that were
>    already cached.
> - mail attachment detection keywords not saved with maildir.
> - dovecot.index.cache may have grown excessively large in some
>    situations. This happened especially when using autoexpunging with
>    lazy_expunge folders. Also with mdbox format in general the cache file
>    wasn't recreated as often as it should have.
> - Autoexpunged mails weren't immediately deleted from the disk. Instead,
>    the deletion from disk happened the next time the folder was opened.
>    This could have caused unnecessary delays if the opening was done by
>    an interactive IMAP session.
> - Dovecot's TCP connections sometimes add extra 40ms latency due to not
>    enabling TCP_NODELAY. HTTP and SMTP/LMTP connections weren't
>    affected, but everything else was. This delay wasn't always visible -
>    only in some situations with some message/packet sizes.
> - imapc: Fix various crash conditions
> - Dovecot builds were not always reproducible.
> - login-proxy: With shutdown_clients=no after config reload the
>    existing connections could no longer be listed or kicked with doveadm.
> - "doveadm proxy kick" with -f parameter caused a crash in some
>    situations.
> - Auth policy can cause segmentation fault crash during auth process
>    shutdown if all auth requests have not been finished.
> - Fix various minor bugs leading into incorrect behaviour in mailbox
>    list index handling. These rarely caused noticeable problems.
> - LDAP auth: Iteration accesses freed memory, possibly crashing
>    auth-worker
> - local_name { .. } filter in dovecot.conf does not correctly support
>    multiple names and wildcards were matched incorrectly.
> - replicator: dsync assert-crashes if it can't connect to remote TCP
>    server.
> - config: Memory leak in config process when ssl_dh setting wasn't
>    set and there was no ssl-parameters.dat file.
>    This caused config process to die once in a while
>    with "out of memory".
> 
> ---
> Aki Tuomi
> Open-Xchange oy
>