August 2019 - dovecot

pigeonhole/lda accessing -m folder
by matthias lay 12 Sep '19

12 Sep '19

Hi all, anybody knows, if there is a way to acces the folder from a call like this deovecot-lda -m destfolder from within a sieve script? thx in advance matze

5 9

Case sensitive problem for vacation with dovecot lmtp pigeonhole
by kadafax＠gmail.com 11 Sep '19

11 Sep '19

Hi list, This issue was raised here by John Fawcett on 12/02/19 but got no response. So, as I'm facing the same issue, I would like to try again: When using the vacation sieve extension, if I send an email to user.name(a)mydomain.com it will work, but not to User.Name(a)mydomain.com. Is there a way to make the user part case insensitive so that the vacation auto-reply is fired whatever the way user part is written ? doveconf -n output: # 2.3.5.1 (7ec6d0ade): /usr/local/etc/dovecot/dovecot.conf # Pigeonhole version 0.5.5 (2483b085) # OS: Linux 3.10.0-957.5.1.el7.x86_64 x86_64 CentOS Linux release 7.6.1810 (Core) ext4 # Hostname: myserver.mydomain.com auth_master_user_separator = * auth_username_chars = abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ01234567890.-_@* auth_verbose = yes debug_log_path = /var/log/dovecot-debug.log default_client_limit = 10640 default_process_limit = 2128 default_vsz_limit = 0 hostname = mydomain.com info_log_path = /var/log/dovecot.log lda_mailbox_autocreate = yes lda_mailbox_autosubscribe = yes listen = * log_path = /var/log/dovecot-error.log login_greeting = Welcome mail_gid = vmail mail_location = maildir:/var/vmail/%Ln mail_plugins = quota fts fts_lucene mail_uid = vmail managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext namespace inbox { inbox = yes location = maildir:/var/vmail/%Ln mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox Sent { auto = subscribe special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { auto = subscribe special_use = \Trash } prefix = type = private } passdb { args = /usr/local/etc/dovecot/deny-users deny = yes driver = passwd-file } passdb { args = /usr/local/etc/dovecot/master-users driver = passwd-file master = yes pass = yes } passdb { args = /usr/local/etc/dovecot/dovecot-ldap.conf.ext driver = ldap } plugin { fts = lucene fts_autoindex = yes fts_lucene = whitespace_chars=@. quota = maildir:User quota quota_rule = *:storage=30GB quota_rule2 = Trash:storage=+200M quota_warning = storage=95%% quota-warning 95 %u quota_warning2 = storage=80%% quota-warning 80 %u sieve = /var/sieve-scripts/%Ln.sieve sieve_dir = /var/vmail/%Ln/home/sieve } postmaster_address = postmaster(a)mydomain.com protocols = imap pop3 lmtp sieve sieve quota_full_tempfail = yes service auth-worker { user = $default_internal_user } service auth { unix_listener /var/spool/postfix/private/auth { mode = 0777 user = vmail } } service imap-login { inet_listener imaps { port = 993 ssl = yes } process_min_avail = 10 } service imap { process_limit = 2128 } service lmtp { executable = lmtp -L process_min_avail = 15 unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0600 user = postfix } } service managesieve-login { inet_listener sieve { port = 4190 } } service pop3-login { inet_listener pop3s { port = 995 ssl = yes } } service quota-warning { executable = script /usr/local/bin/quota-warning.sh user = nobody } ssl_cert = </etc/letsencrypt/live/myserver.mydomain.com/fullchain.pem ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it userdb { args = /usr/local/etc/dovecot/dovecot-ldap-userdb.conf.ext driver = ldap override_fields = uid=vmail gid=vmail home=/var/vmail/%Ln/home } protocol imap { mail_max_userip_connections = 30 mail_plugins = quota fts fts_lucene imap_quota } protocol lmtp { info_log_path = /var/log/dovecot-lmtp.log log_path = /var/log/dovecot-lmtp-errors.log mail_plugins = quota fts fts_lucene sieve } protocol sieve { mail_max_userip_connections = 20 }

2 2

Dovecot Director upgrade from 2.2 to 2.3
by Alessio Cecchi 10 Sep '19

10 Sep '19

Hi, I have a setup with 3 Dovecot Director v2.2.36 and director_consistent_hashing = yes ;-) Now I would like to upgrade to 2.3.7, first only Director and after also Backend. Can works fine a ring of director with mixed 2.2 and 2.3 version? Mi idea is to setup a new Director server with 2.3, stop one server with 2.2 and insert the new 2.3 in the current ring to check if works fine. If all works fine I will replace all Director 2.2 with 2.3 version. Thanks -- Alessio Cecchi Postmaster @ http://www.qboxmail.it https://www.linkedin.com/in/alessice

2 6

CVE-2019-11500: Critical vulnerability in Dovecot and Pigeonhole
by Aki Tuomi 04 Sep '19

04 Sep '19

Dear subscribers, we have been made aware of critical vulnerability in Dovecot and Pigeonhole. --- Open-Xchange Security Advisory 2019-08-14 Product: Dovecot Vendor: OX Software GmbH Internal reference: DOV-3278 Vulnerability type: Improper input validation (CWE-20) Vulnerable version: All versions prior to 2.3.7.2 and 2.2.36.4 Vulnerable component: IMAP and ManageSieve protocol parsers (before and after login) Report confidence: Confirmed Solution status: Fixed by Vendor Fixed version: 2.3.7.2, 2.2.36.4 Researcher credits: Nick Roessler and Rafi Rubin, University of Pennsylvania Vendor notification: 2019-04-13 Solution date: 2019-06-05 Public disclosure: 2019-08-28 CVE reference: CVE-2019-11500 CVSS: 8.1 (CVSS3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H) Vulnerability Details: IMAP and ManageSieve protocol parsers do not properly handle NUL byte when scanning data in quoted strings, leading to out of bounds heap memory writes. Risk: This vulnerability allows for out-of-bounds writes to objects stored on the heap up to 8096 bytes in pre-login phase, and 65536 bytes post-login phase, allowing sufficiently skilled attacker to perform complicated attacks that can lead to leaking private information or remote code execution. Abuse of this bug is very difficult to observe, as it does not necessarily cause a crash. Attempts to abuse this bug are not directly evident from logs. Steps to reproduce: This bug is best observed using valgrind to see the out of bounds read with following snippet: perl -e 'print "a id (\"foo\" \"".("x"x1021)."\\A\" \"bar\" \"\000".("x"x1020)."\\A\")\n"' | nc localhost 143 Solution: Operators should update to the latest Patch Release. There is no workaround for the issue. --- Aki Tuomi Open-Xchange oy

8 14

Dovecot 2.3.7 - char "-" missing
by Domenico Pastore 03 Sep '19

03 Sep '19

Hello, i have update dovecot from version 2.2.15 to 2.3.7.2. I have a problem with mine java software because there is a different response when open connection to doveadm. I need open socket to doveadm for get imap quota of a mailbox. With version 2.2.15: # telnet 192.160.10.4 924 Trying 192.160.10.4... Connected to 192.160.10.4. Escape character is '^]'. - With version 2.3.7.2: # telnet 192.160.10.3 924 Trying 192.160.10.3... Connected to 192.160.10.3. Escape character is '^]'. The difference is "-" character. The version 2.3.7 not respond with "-" character after opening the connection. Is it possible to add the character again with a parameter? Why did doveadm's answer change? Br Domenico

3 2

Segfault with error 4 in doveadm-server
by holger＠dehnhardt.org 03 Sep '19

03 Sep '19

I set up dovecot on two servers with replication enabled. The replication is over a vpn connection. I get massive segfaults from doveadm-server every few minutes. dmesg: doveadm-server[30030]: segfault at 0 ip 0000557fa16d2e62 sp 00007ffdcaafec50 error 4 in doveadm-server[557fa16a3000+41000] [486397.225636] Code: 40 03 4c 8d 3c c3 48 8d 44 24 18 48 89 44 24 08 0f 1f 84 00 00 00 00 00 49 8b bc 24 60 01 00 00 e8 e3 2a 00 00 48 89 44 24 18 <48> 8b 13 48 8d 35 c4 8d 00 00 48 89 c7 e8 2c 2b 00 00 31 c0 c6 45 mail.err dovecot: doveadm: Fatal: master: service(doveadm): child 29507 killed with signal 11 (core dumps disabled) I am absolutely unaware of how I can come to the cause of this error. Can anyone give me a hint? ----------------------------- Configuration: # 2.2.13: /etc/dovecot/dovecot.conf # OS: Linux 5.1.14-xen x86_64 Debian 8.11 auth_debug = yes disable_plaintext_auth = no doveadm_password = xxxx doveadm_port = 4711 listen = * mail_access_groups = vmail mail_gid = vmail mail_home = /var/vmail/%d/%n mail_location = maildir:~/mail mail_plugins = " notify replication" mail_uid = vmail managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date ihave namespace inbox { inbox = yes location = mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox Junk { auto = subscribe special_use = \Junk } mailbox Sent { special_use = \Sent } mailbox Trash { auto = subscribe special_use = \Trash } prefix = } passdb { args = /etc/dovecot/dovecot-ldap.conf.ext driver = ldap } plugin { mail_log_events = delete undelete expunge copy mailbox_delete mailbox_rename mail_log_fields = uid box msgid size mail_replica = tcp:backup-vpn.local:12345 sieve = ~/.dovecot.sieve sieve_after = ~/sieve/after sieve_before = ~/sieve/before sieve_default = /var/vmail/%d/default.sieve sieve_dir = ~/sieve } protocols = " imap sieve pop3" service aggregator { fifo_listener replication-notify-fifo { mode = 0666 user = vmail } unix_listener replication-notify { mode = 0666 user = vmail } } service auth { unix_listener auth-client { group = vmail mode = 0660 user = vmail } unix_listener auth-userdb { mode = 0666 user = vmail } } service config { unix_listener config { user = vmail } } service doveadm { client_limit = 1 idle_kill = 0 inet_listener { address = master-vpn.local port = 12345 } process_limit = 0 process_min_avail = 0 user = vmail } service replicator { client_limit = 0 drop_priv_before_exec = no idle_kill = 4294967295 secs process_limit = 1 process_min_avail = 0 service_count = 0 unix_listener replicator-doveadm { group = vmail mode = 0666 user = dovecot } vsz_limit = 8 G } ssl_cert = </etc/ssl/certs/xxx.cert ssl_key = </etc/ssl/private/xxx.key userdb { args = /etc/dovecot/dovecot-ldap.conf.ext driver = ldap } protocol sieve { managesieve_implementation_string = Dovecot Pigeonhole managesieve_max_line_length = 65536 } protocol lda { mail_plugins = " notify replication acl sieve" } protocol imap { mail_plugins = " notify replication acl" }

3 6

LMTP Post login script for acl_groups
by lists＠mlserv.org 03 Sep '19

03 Sep '19

Hi, I use a post login script for imap, to fetch acl groups from LDAP. Because Dovecot can only deal with a single value, which must be a comma seperated list of groups, I decided to use a post login script do deal with multi values in LDAP: This looks like this in LDAP: rnsMSACLGroup: admin rnsMSACLGroup: automx rnsMSACLGroup: amavis rnsMSACLGroup: postfix rnsMSACLGroup: dovecot rnsMSACLGroup: rspamd rnsMSACLGroup: powerdns rnsMSACLGroup: sogo rnsMSACLGroup: zabbix rnsMSACLGroup: dane-users rnsMSACLGroup: gentoo rnsMSACLGroup: openbsd My post login script looks like this: --------------------------------------------------------- #!/bin/sh BINDDN='cn=dovecot-postlogin,ou=people,ou=it,dc=roessner-net,dc=de' BINDPWFILE='/etc/dovecot/ldap-postlogin.secret' BASE='ou=people,ou=it,dc=roessner-net,dc=de' LDAPSEARCH="/usr/bin/ldapsearch" AWK="/usr/bin/awk" test -x ${LDAPSEARCH} || exec "$@" test -x ${AWK} || exec "$@" ACL_GROUPS=$( ${LDAPSEARCH} -LLL -ZZ -y ${BINDPWFILE} -xD ${BINDDN} -b ${BASE} "(rnsMSDovecotUser=${USER})" rnsMSACLGroup | \ grep rnsMSACLGroup | \ ${AWK} -vORS=, '{ print $2 }' | \ sed 's/,$/\n/' ) export ACL_GROUPS export USERDB_KEYS="${USERDB_KEYS} acl_groups" exec "$@" --------------------------------------------------------- This script is included in imap-postlogin executables and works for logged in users. But it does not work for LMTP. LMTP itself seems not to have any permissions to access the folders associated with these groups. I thought, I simply could add the imap-postlogin block to lmtp-postlogin and that would work, but it doesn't. So here is the question: What am I missing in Dovecot that LMTP can also have ACL_GROUPS like the imap service? Here is my config (non-defaults): --------------------------------------------------------- doveconf -n # 2.3.7.1 (0152c8b10): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.7.1 (db5c74be) # OS: Linux 4.19.44-gentoo x86_64 Gentoo Base System release 2.6 # Hostname: mx.roessner-net.de auth_cache_size = 64 M auth_master_user_separator = * auth_mechanisms = plain login auth_ssl_username_from_cert = yes auth_verbose = yes default_client_limit = 5000 default_process_limit = 500 default_vsz_limit = 512 M disable_plaintext_auth = no hostname = mail.roessner-net.de imap_client_workarounds = tb-extra-mailbox-sep tb-lsub-flags imap_max_line_length = 4 M lda_mailbox_autocreate = yes lda_mailbox_autosubscribe = yes lmtp_rcpt_check_quota = yes login_log_format_elements = user=<%u> method=%m rip=%r lip=%l mpid=%e %c %k mail_access_groups = vmail mail_attachment_dir = /var/mail/virtual/copymail/attachments mail_gid = vmail mail_location = sdbox:~/sdbox mail_max_keyword_length = 4096 mail_plugins = quota acl fts fts_lucene zlib mail_log notify mail_privileged_group = mail mail_save_crlf = yes mail_uid = vmail managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext vacation-seconds imapsieve vnd.dovecot.imapsieve mdbox_preallocate_space = yes mdbox_rotate_size = 128 M namespace { list = children location = sdbox:%%h/sdbox prefix = Shared/%%u/ separator = / subscriptions = no type = shared } namespace { hidden = no list = children location = maildir:/var/mail/virtual/public:INDEXPVT=~/Maildir/public prefix = Public/ separator = / subscriptions = no type = public } namespace inbox { inbox = yes location = mailbox Archive { auto = subscribe special_use = \Archive } mailbox "Deleted Messages" { special_use = \Trash } mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox Junk-E-Mail { special_use = \Junk } mailbox Junk { auto = subscribe special_use = \Junk } mailbox Sent { auto = subscribe special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { auto = subscribe special_use = \Trash } prefix = separator = / type = private } passdb { args = /etc/dovecot/master-users driver = passwd-file master = yes pass = yes } passdb { args = /etc/dovecot/dovecot-ldap.conf.ext driver = ldap } plugin { acl = vfile:/etc/dovecot/dovecot-acl:cache_secs=300 acl_shared_dict = file:/var/mail/virtual/shared-mailboxes.db fts = lucene fts_autoindex = yes fts_lucene = whitespace_chars=@. imapsieve_mailbox1_before = file:/etc/dovecot/sieve/rspamd.d/report-spam.sieve imapsieve_mailbox1_causes = COPY FLAG imapsieve_mailbox1_name = Junk imapsieve_mailbox2_before = file:/etc/dovecot/sieve/rspamd.d/report-ham.sieve imapsieve_mailbox2_causes = COPY imapsieve_mailbox2_from = Junk imapsieve_mailbox2_name = * mail_log_events = delete undelete expunge copy save mailbox_create mailbox_delete mailbox_rename mail_log_fields = box msgid quota = count:User quota quota_grace = 10%% quota_rule = *:storage=300M:messages=20000 quota_rule2 = Trash:storage=+500M quota_rule3 = Sent:storage=+2G quota_rule4 = Archive:storage=+2G quota_status_nouser = DUNNO quota_status_overquota = 552 5.2.2 Mailbox is full quota_status_success = DUNNO quota_vsizes = yes quota_warning = storage=95%% quota-warning 95 %u quota_warning2 = storage=80%% quota-warning 80 %u quota_warning3 = -storage=100%% quota-warning below %u sieve = file:~/sieve;active=~/.dovecot.sieve sieve_after = /etc/dovecot/sieve/after sieve_before = /etc/dovecot/sieve/before sieve_extensions = +vacation-seconds sieve_global_extensions = +vnd.dovecot.pipe +vnd.dovecot.execute +vnd.dovecot.debug sieve_pipe_bin_dir = /usr/bin sieve_plugins = sieve_imapsieve sieve_extprograms sieve_vacation_default_period = 10d sieve_vacation_max_period = 30d sieve_vacation_min_period = 1h zlib_save = gz zlib_save_level = 6 } protocols = imap pop3 lmtp submission sieve service auth-worker { extra_groups = ssl-cert unix_listener auth-worker { mode = 0600 user = vmail } user = vmail } service auth { extra_groups = ssl-cert unix_listener /var/spool/postfix-submission/private/auth { group = postfix mode = 0666 user = postfix } unix_listener auth-userdb { mode = 0600 user = vmail } user = vmail } service config { unix_listener config { mode = 0600 user = vmail } } service dict { unix_listener dict { mode = 0600 user = vmail } } service imap-login { inet_listener imap { address = 127.0.0.1 134.255.226.248 ::1 2a05:bec0:28:1:134:255:226:248 } inet_listener imaps { port = 0 } } service imap-postlogin { executable = script-login /usr/local/bin/dovecot-masteruser.sh /usr/local/bin/dovecot-lastlogin.sh /usr/local/bin/dovecot-aclgroups.sh user = vmail } service imap { executable = imap imap-postlogin } service lmtp-postlogin { executable = script-login /usr/local/bin/dovecot-aclgroups.sh user = vmail } service lmtp { executable = lmtp lmtp-postlogin inet_listener lmtp { address = 127.0.0.1 port = 24 } unix_listener /var/spool/postfix/private/lmtp-dovecot { group = postfix mode = 0660 user = postfix } } service managesieve-login { inet_listener sieve { address = 127.0.0.1 134.255.226.248 ::1 2a05:bec0:28:1:134:255:226:248 } } service pop3-login { inet_listener pop3 { address = 127.0.0.1 134.255.226.248 ::1 2a05:bec0:28:1:134:255:226:248 } inet_listener pop3s { port = 0 } } service quota-status { client_limit = 1 executable = quota-status -p postfix inet_listener { address = 127.0.0.1 port = 12340 } } service quota-warning { executable = script /usr/local/bin/quota-warning.sh extra_groups = mail unix_listener quota-warning { group = vmail mode = 0600 user = vmail } user = vmail } ssl_cert = </etc/ssl/mail.roessner-net.de/cert/fullchain.pem ssl_cipher_list = ALL:!DH:!kRSA:!SRP:!kDHd:!DSS:!aNULL:!eNULL:!EXPORT:!DES:!3DES:!MD5:!PSK:!RC4:!ADH:!LOW@STRENGTH ssl_client_cert = </etc/ssl/mail.roessner-net.de/cert/fullchain.pem ssl_client_key = # hidden, use -P to show it ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it ssl_min_protocol = TLSv1.2 ssl_prefer_server_ciphers = yes submission_client_workarounds = whitespace-before-path submission_relay_host = mail.roessner-net.de submission_relay_port = 5870 submission_relay_ssl = starttls submission_relay_trusted = yes userdb { args = /etc/dovecot/dovecot-ldap-userdb.conf.ext driver = ldap } verbose_proctitle = yes protocol lmtp { mail_plugins = quota acl fts fts_lucene zlib mail_log notify sieve } protocol lda { mail_plugins = quota acl fts fts_lucene zlib mail_log notify sieve } protocol imap { mail_max_userip_connections = 50 mail_plugins = quota acl fts fts_lucene zlib mail_log notify imap_quota imap_acl imap_zlib imap_sieve } protocol submission { login_greeting = ESMTP } --------------------------------------------------------- Thanks for any help in advance Christian

3 15

Re: Message delivered twice caused by an LMTP error "Got unexpected reply" during upgrade to 2.3
by Gabriele Nencioni 02 Sep '19

02 Sep '19

>>> On 08/09/2018 09:12 AM, Stephan Bosch wrote >>>>>> Can you make a pcap log of the LMTP communication between the two >>>>>> Dovecot hosts? That may give me a clue on which side of the >>>>>> communication is causing the issue. >>>>> Yes sure, where I can send it? >>>>> Here on list or at your address? >>>> >>>> Just send it to me. On 08/16/2018 10:21 AM, Stephan Bosch wrote: > Op 16/08/2018 om 09:46 schreef Gabriele Nencioni: >> On 08/15/2018 06:39 PM, Stephan Bosch wrote: >>> Op 15-8-2018 om 17:19 schreef Stephan Bosch: >>>> >>>> Op 13-8-2018 om 15:50 schreef Gabriele Nencioni: >>>>> So the scenario seems to be: >>>>> the error occurs between old directors and new backends >>>>> and between the new backends and the smtp submission_host (for >>>>> redirection) >>>>> and using the pipeline capability and attaching a file >>>>> >>>>> Let me know if you need more info >>>> In this case it is possible to obtain a debug log by enabling >>>> mail_debug=yes. Can you obtain a full debug log for such a failing >>>> submission session? >> Ok! It is attached. > > That is just weird. Dovecot reports that it cannot fully send the last > bits of the message and right thereafter the reply is received, which > Dovecot then interprets as out-of-sequence. The PCAP files tell me the > final CRLF.CRLF is actually sent to the other side, but somehow Dovecot > thinks it couldn't do that yet. > > Is this problem occurring for any and all SMTP client interactions, or > just every once in a while? Unfortunately it occurs just every once in a while and it is weird because at the second attempt the message is successful delivered or redirected. >>> Also, I don't see anything weird in the PCAP files: the command-reply >>> sequence is OK. This means that this is likely a bug in the current >>> Dovecot version. Those debug logs should tell me more. >> Ok! Which version of dovecot do you suggest to install? >> On debian current stable (stretch) repository there is the version >> number 2.2.27, have we to install it? > > If you're facing big trouble it is usually best to revert to the > previous version that worked I guess. Ok I'm agree! So, about you, which version can I try to install the 2.2.27 or the previous release of the 2.3 version such as v2.3.2 2018-06-29 or v2.3.1 2018-02-29? Regards, -- Gabriele Nencioni System Administrator eml gabriele.nencioni(a)register.it

2 6

purge causing reappearing mails?
by sch tel 02 Sep '19

02 Sep '19

3 3

flags not synced correctly with dovecot sync (dsync)
by Dan Christensen 31 Aug '19

31 Aug '19

I'm running dovecot 2.3.4.1 from https://repo.dovecot.org/ on Ubuntu 18.04 on three machines that I'll call server, laptop1 and laptop2. Both laptop1 and laptop2 run dovecot sync against server to keep local copies of my imap folders. Even when I initially had only two machines, laptop1 and server, I occasionally noticed that flags were lost, usually custom flags used by Gnus, but I couldn't reliably reproduce the problem. Now that I have two laptops syncing against the server, the problem has gotten worse and I figured out a way to reproduce it: - on server: create new IMAP folder test, and put two read messages in it - on laptop1: doveadm sync -u user -l 10 -m test -f user@server - on laptop2: doveadm sync -u user -l 10 -m test -f user@server At this point, all three machines show the two messages M1 and M2 as being read. - on laptop1: mark message M1 unread - on laptop2: mark message M2 unread - on laptop1: doveadm sync -u user -l 10 -m test -f user@server Both laptop1 and server have M1 unread, M2 read, as expected. - on laptop2: doveadm sync -u user -l 10 -m test -f user@server Now laptop2 and server have M1 *read*, M2 unread. - on laptop1: doveadm sync -u user -l 10 -m test -f user@server Now laptop1 and the server have both M1 and M2 *read*. - on laptop2: doveadm sync -u user -l 10 -m test -f user@server Now laptop2 has both read as well. The two lines that say "*read*" are wrong in my opinion. dsync propagated a read mark to an unread message, even though that message was marked unread more recently than it was marked read. I usually use stateful sync, and get many related problems. I just did a test in which M1 and M2 started out read, and I started with empty files named dstate.test on laptop1 and laptop2. Then I did the above procedure, using the command doveadm sync -u user -l 10 -m test -s "`cat dstate.test`" user@server > dstate.test At the end, laptop2 and server had both messages unread (which is good), but laptop1 had only M1 unread, and repeated runs of the sync command did not correct this. So the stateful sync failed to detect a change. Are these bugs in dovecot? Is there more information that I can provide? The output of doveconf -n on one machine is below, and the others are almost identical. Thanks for any help! Dan # 2.3.4.1 (3c0b8769e): /etc/dovecot/dovecot.conf # OS: Linux 4.15.0-45-generic x86_64 Ubuntu 18.04.1 LTS # Hostname: laptop2 auth_mechanisms = plain login listen = 127.0.0.1 mail_index_log2_max_age = 10 days mail_index_log_rotate_min_age = 1 days mail_index_log_rotate_min_size = 300 k mail_location = maildir:~/Maildir namespace inbox { inbox = yes location = mailbox Drafts { special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Sent { special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { special_use = \Trash } prefix = } passdb { args = scheme=CRYPT username_format=%u /etc/dovecot/users driver = passwd-file } protocols = imap service imap-login { inet_listener imap { address = * port = 143 } inet_listener imaps { address = * port = 943 ssl = yes } } service imap { process_limit = 25 } ssl_cert = </etc/dovecot/private/dovecot.pem ssl_client_ca_dir = /etc/ssl/certs ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it userdb { args = username_format=%u /etc/dovecot/users driver = passwd-file } protocol lda { postmaster_address = [elided] } protocol imap { mail_max_userip_connections = 20 }

3 8