October 2017 - dovecot

Strange "IMAP connection broken (server response)" errors
by Jozsef Kadlecsik 20 Mar '18

20 Mar '18

Hello, We upgraded one of our dovecot servers to debian stretch with dovecot 2.2.27 and since then one of our users has been experiencing random IMAP failures. We enabled raw logging at the server side and it shows normal IMAP commands/responses: 1507292522.222427 * 6 FETCH (FLAGS () BODYSTRUCTURE ("text" "plain" ("charset" "us-ascii") NIL NIL "7bit" 4645 112 NIL NIL NIL NIL)) 1507292522.222653 00000011 OK Fetch completed (0.006 + 0.000 secs). On the client side the user runs alpine and the corresponding debug lines: IMAP DEBUG 14:22:02.216167: 00000011 FETCH 6 (BODYSTRUCTURE FLAGS) 14:22:02.217396 IMAP 14:22:02 10/6 mm_notify bye: {[127.0.0.1]:1555/imap/user="ha4aa"}INBOX: [CLOSED] IMAP connection broken (server response) 14:22:02.217471 IMAP 14:22:02 10/6 mm_log error: [CLOSED] IMAP connection broken (server response) The "[127.0.0.1]:1555/imap/user="ha4aa" part in the log comes from an socat inserted between the client and the server to check independetly the imap session. According to socat, the server response didn't reach the client!: 00000010 OK Fetch completed (0.005 + 0.000 secs).\r > 2017/10/06 14:22:02.216299 length=40 from=845 to=884 00000011 FETCH 6 (BODYSTRUCTURE FLAGS)\r and here ends the socat log, the server response didn't reach the client. The same alpine package is used against older dovecot servers from debian jessie and works flawlessly. The server and client are both KVM guests and there's no any content filtering software between them. There's no corresponding error in the dovecot log file and dovecot didn't regard the connection broken and detected client close: ... Oct 6 14:19:44 mail2 dovecot: imap(ha4aa): Debug: Mailbox INBOX: Opened mail UID=55244 because: MIME part Oct 6 14:22:02 mail2 dovecot: imap(ha4aa): Connection closed in=797 out=73151 We are out of the ideas what can be the reason for the random lost server responses. Any help is appreciated! Best regards, Jozsef -- E-mail : kadlecsik.jozsef(a)wigner.mta.hu PGP key: http://www.kfki.hu/~kadlec/pgp_public_key.txt Address: Wigner Research Centre for Physics, Hungarian Academy of Sciences H-1525 Budapest 114, POB. 49, Hungary

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Non-destructive deduplication
by Tristan Miller 15 Jan '18

15 Jan '18

Greetings. I use Dovecot 2.2.29.1 as my IMAP server. Owing to a bug in my mail client [1], several unique messages (mostly in my Sent folder) have duplicate Message-ID headers. Dovecot itself doesn't seem to be bothered by this, though my mail client is confused by the false duplicates. (It screws up the threading display, and results in data loss when I run the client's deduplication filter.) I would like to change the Message-ID headers in the "duplicate" message files stored in my IMAP server so that they are unique. I realize that this has disadvantages of its own, but I can't think of a better alternative. So this leads me to two questions: 1) Will Dovecot get confused if I simply open the message files in a text editor and manually change their Message-ID headers? If so, how should I go about changing the Message-ID headers? 2) Does there exist any tool that will scan a maildir folder to find messages with duplicate Message-IDs, and automatically rewrite the Message-ID headers so that they are (probably) unique? I could probably kludge together a quick shell script, but if someone's already gone to the trouble of writing such a tool and making it relatively robust, I'd rather use that instead. Regards, Tristan [1] http://www.thewildbeast.co.uk/claws-mail/bugzilla/show_bug.cgi?id=3828 -- =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Tristan Miller Free Software developer, ferret herder, logologist https://logological.org/ =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

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Managesieve cannot access script store
by dovelist 11 Jan '18

11 Jan '18

Hi, I am trying to get sieve working on a new OpenSuse leap 42.2 install. On my 'old' OpenSuse 13.2 machine it worked fine. The problem is that Managesieve can't access the script store and won't let me create any script. It says permission denied on ~/sieve directory. See log below. I 've activated debug logging, but that doesn't give any clues to me. Also, I've set the directory accessible to all, but Managesieve still complains. > cd ~ > ls -l drwx------ 1 rogier users 8340 5 feb 16:54 Maildir drwxrwxrwx 1 rogier users 24 5 feb 18:38 sieve To rule out client issues (kmail) I tested also with Manual TLS Login as described in: http://wiki2.dovecot.org/Pigeonhole/ManageSieve/Troubleshooting Same result. I am puzzled. I can't find anything wrong in the dovecot configuration. The output of dovecot -n is shown below. Hope someone has a solution. A lot of mail is waiting to get sorted... Best Regards, Rogier The log: feb 05 20:22:18 p150 dovecot[12120]: managesieve-login: Login: user=<rogier>, method=PLAIN, rip=192.168.0.18, lip=192.168.0.20, mpid=12135, TLS, session=<gmb0bs1H5q/AqAAS> feb 05 20:22:18 p150 dovecot[12120]: managesieve(rogier): Debug: Effective uid=1000, gid=100, home=/home/rogier feb 05 20:22:18 p150 dovecot[12120]: managesieve(rogier): Debug: Namespace inbox: type=private, prefix=, sep=, inbox=yes, hidden=no, list=yes, subscriptions=yes location=maildir:~/Maildir feb 05 20:22:18 p150 dovecot[12120]: managesieve(rogier): Debug: maildir++: root=/home/rogier/Maildir, index=, indexpvt=, control=, inbox=/home/rogier/Maildir, alt= feb 05 20:22:18 p150 dovecot[12120]: managesieve(rogier): Debug: sieve: Pigeonhole version 0.4.15 (97b3da0) initializing feb 05 20:22:18 p150 dovecot[12120]: managesieve(rogier): Debug: sieve: include: sieve_global is not set; it is currently not possible to include `:global' scripts. feb 05 20:22:18 p150 dovecot[12120]: managesieve(rogier): Debug: sieve: file storage: Using active Sieve script path: /home/rogier/.dovecot.sieve feb 05 20:22:18 p150 dovecot[12120]: managesieve(rogier): Debug: sieve: file storage: Using script storage path: /home/rogier/sieve/ feb 05 20:22:18 p150 dovecot[12120]: managesieve(rogier): Debug: sieve: file storage: Using permissions from /home/rogier/sieve/: mode=0777 gid=-1 feb 05 20:22:18 p150 dovecot[12120]: managesieve(rogier): Debug: sieve: file storage: Relative path to sieve storage in active link: sieve/ feb 05 20:22:18 p150 dovecot[12120]: managesieve(rogier): Debug: sieve: file storage: sync: Synchronization active feb 05 20:22:18 p150 dovecot[12120]: managesieve(rogier): Error: sieve: file storage: Failed to list scripts: opendir(/home/rogier/sieve) failed: Permission denied Output of dovecot -n: # 2.2.25 (7be1766): /etc/dovecot/dovecot.conf # Pigeonhole version 0.4.15 (97b3da0) # OS: Linux 4.4.36-8-default x86_64 openSUSE 42.2 (x86_64) auth_username_format = %Ln base_dir = /var/run/dovecot/ mail_debug = yes mail_location = maildir:~/Maildir 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 = 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 { driver = pam } plugin { sieve = file:~/sieve/;active=~/.dovecot.sieve sieve_trace_debug = yes } protocols = imap lmtp sieve service lmtp { unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0600 user = postfix } } ssl = required ssl_cert = </etc/ssl/private/dovecot.crt ssl_dh_parameters_length = 2048 ssl_key = </etc/ssl/private/dovecot.pem ssl_options = no_compression ssl_prefer_server_ciphers = yes userdb { driver = passwd } verbose_ssl = yes protocol lmtp { mail_plugins = sieve postmaster_address = postmaster@xxxxxxxxxxxxxx }

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Locks directory change
by Federico Bartolucci 08 Jan '18

08 Jan '18

Hello, it's the first time for me writing to the list, I'm trying to change the location into which the Dovecot's locks are done reserving a special temporary directory on an other partition, then adding to the dovecont.conf the line: mail_location = maildir:~/Maildir:VOLATILEDIR=/tmp_lock/%2.256Nu/%u so that through the VOLATILEDIR directive the locks should be written in this path. We observe though that the locks for many users are still done in the real maildir (NFS mounted filesystem) as if in some situations this instruction is not effective. Anybody knows if are there other things to change or to do or what could be the reason? (for instance to login in a specific way or doing a particular operation). Regards, Federico

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Sieve can't move messages in a public namespace
by Paolo 02 Jan '18

02 Jan '18

Hello, my dovecot version is 2.1.17 I've configured some public namespaces (config attached). When a mail arrives at a certain mail address, that mail is handled by dovecot lmtp server and a sieve script is executed that shuold move the message in one of the namespaces. This is the script: require "fileinto"; if header :contains "From" "example(a)example.com" { fileinto :create "Cond-UFF_FORNITORI/CONTABILITA/Inviata"; } else { fileinto :create "Cond-UFF_FORNITORI/CONTABILITA/Ricevuta"; } The problem is that the sieve script fails with the error: sieve: info: started log at Jun 27 12:42:28. error: msgid=<c9154db4-ff68-52a3-2639-11f09f225f68(a)fcr.re.it>: failed to store into mailbox 'Cond-UFF_FORNITORI/CONTABILITA/Ricevuta': Mailbox doesn't exist: Cond-UFF_FORNITORI/CONTABILITA/Ricevuta. I double checked config, dovecot documentation, sieve documentation, ACL, filesystem paths, filesystem permissions, etc. etc. I'm pretty sure it's all right. So why isn't sieve working? Thanks if you bother to answer & Cheers Paolo

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ManageSieve: authenticate "EXTERNAL" not behaving correctly
by Marc Weustink 30 Nov '17

30 Nov '17

Hi, I've enabled client certificate authentication for imap and managesieve. When I use Thunderbird with the sieve plugin it tries to login, but times out. Initially I reported this to the sieve plugin, but we came to the conclusion that it managesieve is misbehaving. https://github.com/thsmi/sieve/issues/94 Thunderbird (win10-64) 52.4.0 (32bit) Sieve 0.2.3k Dovecot (Ubuntu 16.04.3 LTS) 2.2.33.1-1 (sid) What happens is the following (p=plugin sends m=managesieve sends) p:authenticate "EXTERNAL" "" m:"" The response is unexpected. According to RFC 5804 an empty challenge/response is sent as an empty string. So I would expect: p:authenticate "EXTERNAL" "" m:OK "Logged in." With the use of gnutls-cli I could reproduce (c=I send m=managesieve sends) gnutls-cli --starttls --x509keyfile marc_mail.key --x509certfile marc_mail.crt -p sieve 172.17.1.4 ... m:OK "TLS negotiation successful." c:authenticate "EXTERNAL" "" m:"" c:"" m:OK "Logged in." However if I try the "imap" syntax (rfc4959) I get logged in at once ... m:OK "TLS negotiation successful." c:authenticate "EXTERNAL" "=" m:OK "Logged in." Note that this is an imap only extention, "=" is an invalid base64 encoding. Marc

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iPhone/iPad IMAP connection bursts causes user+IP exceeded
by Joseph Tam 29 Nov '17

29 Nov '17

I frequently see this from my iPhone/iPad IMAP users: Oct 24 21:30:55 server dovecot: imap-login: Login: user=<user>, ... [... repeated 10 times ...] Oct 24 21:32:54 server dovecot: imap-login: Maximum number of connections from user+IP exceeded (mail_max_userip_connections=12): user=<user> Oct 24 21:32:54 server dovecot: imap(user): Logged out ... [... repeated 11 times ...] These bursts of logins/max/logouts would cycling on for a few minutes. Googling this problem seems to turn up lots of similar complaints about iOS mail mail clients. e.g. https://discussions.apple.com/thread/2547839?tstart=0 iOS mail readers do not limit connections limit as other mailreaders can. I could increase mail_max_userip_connections, but that just moves the goal posts. Using the new rawlog feature in 2.2.26 (thanks Dovecot team!), I was able to see that these connection bursts are caused by clients doing global searches. The rawlogs show each mailbox being SELECT'd and searched (e.g. From header string): 1477369968.730450 2 ID ("name" "iPad Mail" "version" "13G36" "os" "iOS" "os-version" "9.3.5 (13G36)") 1477369968.781932 3 SELECT {mailbox} 1477369968.961636 4 UID SEARCH RETURN (COUNT) 1:* NOT DELETED 1477369969.006087 5 UID SEARCH RETURN (ALL) 1:* NOT DELETED 1477369969.052701 6 UID SEARCH RETURN (ALL) {search-term} NOT DELETED 1477369974.624153 7 LOGOUT Questions: 1) How does this affect the user? I heard from one user that it makes global searches unusable because his reader just spins its wheel. I'm not sure whether this is impatience or this results in failed searches. 2) Is there a client-side fix (e.g. connection limiting)? Apple appears to be intransigent on addressing this. 3) Will maintaining search indices (e.g. solr) help with this? Maybe the searches are taking too long and the connections pile up waiting for previous searches to finish. Thanks, Joseph Tam <jtam.home(a)gmail.com>

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Bug: lmtp proxy does not quote local parts with spaces
by David Zambonini 03 Nov '17

03 Nov '17

There seems to be a bug with RFC822 processing in ltmp proxying that doesn't quote local parts that, for example, contain spaces. director config: director_username_hash = %Ln lmtp_proxy = yes recipient_delimiter = + protocol lmtp { auth_socket_path = director-userdb auth_username_chars = auth_username_format = %Ln passdb { driver = sql args = /etc/director/sql.d/lmtp.ext result_failure = return-fail result_internalfail = return-fail } } lmtp.ext: password_query = SELECT 'y' AS proxy, NULL AS password, 'y' AS nopassword FROM users WHERE userName='%Ln' from exim -> director LMTP network dump: MAIL FROM:<test(a)testdomain.com>\r\n RCPT TO:<"deemzed.uk+Junk E-mail"@mailbox.localhost>\r\n DATA\r\n (etc) .\r\n 501 5.5.4 Invalid parameters\r\n QUIT\r\n from director -> dovecot LMTP network dump: MAIL FROM:<test(a)testdomain.com>\r\n RCPT TO:<deemzed.uk+Junk E-mail>\r\n 501 5.5.4 Invalid.parameters\r\n I'll try to pare down a full config for doveconf that displays this behaviour if required, as currently I have sensitive/extraneous information in there, but this seems fairly cut and dried as a bug to me. -- Dave

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dovecot-2.3 (-git) Warning (Was Re: dovecot Digest, Vol 174, Issue 64)
by Reuben Farrelly 02 Nov '17

02 Nov '17

Hi, On 30/10/2017 7:22 PM, dovecot-request(a)dovecot.org wrote: > Message: 6 > Date: Mon, 30 Oct 2017 10:22:42 +0200 > From: Teemu Huovila <teemu.huovila(a)dovecot.fi> > To: dovecot(a)dovecot.org > Subject: Re: dovecot-2.3 (-git) Warning and Fatal Compile Error > Message-ID: <7d2c0b5b-019a-067c-c6be-f36571ed9a96(a)dovecot.fi> > Content-Type: text/plain; charset=utf-8 > > > > On 30.10.2017 09:10, Aki Tuomi wrote: >> >> >> On 30.10.2017 00:23, Reuben Farrelly wrote: >>> Hi Aki, >>> >>> On 30/10/2017 12:43 AM, Aki Tuomi wrote: >>>>> On October 29, 2017 at 1:55 PM Reuben Farrelly >>>>> <reuben-dovecot(a)reub.net> wrote: >>>>> >>>>> >>>>> Hi again, >>>>> >>>>> Chasing down one last problem which seems to have been missed from my >>>>> last email: >>>>> >>>>> On 20/10/2017 9:22 PM, Stephan Bosch wrote: >>>>>> >>>>>> Op 20-10-2017 om 4:23 schreef Reuben Farrelly: >>>>>>> On 18/10/2017 11:40 PM, Timo Sirainen wrote: >>>>>>>> On 18 Oct 2017, at 6.34, Reuben Farrelly <reuben-dovecot(a)reub.net> >>>>>>>> wrote: >>>>> This problem below is still present in 2.3 -git, as of version >>>>> 2.3.devel >>>>> (6fc40674e) >>>>> >>>>>>>> Secondly, this ssl_dh messages is always printed from doveconf: >>>>>>>> >>>>>>>> doveconf: Warning: please set ssl_dh=</etc/dovecot/dh.pem >>>>>>>> doveconf: Warning: You can generate it with: dd >>>>>>>> if=/var/lib/dovecot/ssl-parameters.dat bs=1 skip=88 | openssl dh >>>>>>>> -inform der > /etc/dovecot/dh.pem >>>>>>>> >>>>>>>> Yet the file is there: >>>>>>>> >>>>>>>> thunderstorm conf.d # ls -la /etc/dovecot/dh.pem >>>>>>>> -rw-r--r-- 1 root root 769 Oct 19 21:55 /etc/dovecot/dh.pem >>>>>>>> >>>>>>>> And the config is there as well: >>>>>>>> >>>>>>>> thunderstorm dovecot # doveconf -P | grep ssl_dh >>>>>>>> ssl_dh = </etc/dovecot/dh.pem >>>>>>>> doveconf: Warning: please set ssl_dh=</etc/dovecot/dh.pem >>>>>>>> doveconf: Warning: You can generate it with: dd >>>>>>>> if=/var/lib/dovecot/ssl-parameters.dat bs=1 skip=88 | openssl dh >>>>>>>> -inform der > /etc/dovecot/dh.pem >>>>>>>> ?? ssl_dh = -----BEGIN DH PARAMETERS----- >>>>>>>> ?? ssl_dh = -----BEGIN DH PARAMETERS----- >>>>>>>> ?? ssl_dh = -----BEGIN DH PARAMETERS----- >>>>>>>> ?? ssl_dh = -----BEGIN DH PARAMETERS----- >>>>>>>> ?? ssl_dh = -----BEGIN DH PARAMETERS----- >>>>>>>> ?? ssl_dh = -----BEGIN DH PARAMETERS----- >>>>>>>> ?? ssl_dh = -----BEGIN DH PARAMETERS----- >>>>>>>> ?? ssl_dh = -----BEGIN DH PARAMETERS----- >>>>>>>> thunderstorm dovecot # >>>>>>>> >>>>>>>> It appears that this warning is being triggered by the presence of >>>>>>>> the ssl-parameters.dat file because when I remove it the warning >>>>>>>> goes away. Perhaps the warning could be made a bit more specific >>>>>>>> about this file being removed if it is not required because at the >>>>>>>> moment the warning message is not related to the trigger. >>>>>>>> >>>>>>>> Thanks, >>>>>>>> Reuben >>>>> Thanks, >>>>> Reuben >>>> It is triggered when there is ssl-parameters.dat file *AND* there is >>>> no ssl_dh=< explicitly set in config file. >>>> >>>> Aki >>> >>> I have this already in my 10-ssl.conf file: >>> >>> lightning dovecot # /etc/init.d/dovecot reload >>> doveconf: Warning: please set ssl_dh=</etc/dovecot/dh.pem >>> doveconf: Warning: You can generate it with: dd >>> if=/var/lib/dovecot/ssl-parameters.dat bs=1 skip=88 | openssl dh >>> -inform der > /etc/dovecot/dh.pem >>> ?* Reloading dovecot configs and restarting auth/login processes >>> ...????? [ ok ] >>> lightning dovecot # >>> >>> However: >>> >>> lightning dovecot # grep ssl_dh conf.d/10-ssl.conf >>> # gives on startup when ssl_dh is unset. >>> ssl_dh=</etc/dovecot/dh.pem >>> lightning dovecot # >>> >>> and the file is there: >>> >>> lightning dovecot # ls -la /etc/dovecot/dh.pem >>> -rw-r--r-- 1 root root 769 Oct 19 19:06 /etc/dovecot/dh.pem >>> lightning dovecot # >>> >>> So it is actually configured and yet the warning still is present. >>> >>> Reuben >> >> Hi! >> >> I gave this a try, and I was not able to repeat this issue. Perhaps you >> are still missing ssl_dh somewhere? >> >> Aki >> > Hello > > Just a guess, but at this point I would recommend reviewing the output of "doveconf -n" to make sure the appropriate settings are present. > > br, > Teemu I still can't see anything amiss. Here's the output from doveconf -n: # 2.3.devel (65ef8330e): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.devel (f4659224) # OS: Linux 4.9.56-x86_64-linode87 x86_64 Gentoo Base System release 2.4.1 auth_mechanisms = plain login auth_socket_path = /var/run/dovecot/auth-userdb auth_username_format = %Ln doveadm_password = # hidden, use -P to show it first_valid_uid = 1000 imap_client_workarounds = tb-lsub-flags tb-extra-mailbox-sep last_valid_uid = 1100 login_log_format_elements = user=<%u> auth-method=%m remote=%r local=%l %k login_trusted_networks = 192.168.0.0/16 mail_location = maildir:~/Maildir mail_plugins = stats notify replication fts fts_lucene 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 = 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 = failure_show_msg=yes %s driver = pam } plugin { fts = lucene fts_autoindex = yes fts_languages = en fts_lucene = whitespace_chars=@. mail_replica = tcps:inside-mail.reub.net:4813 replication_full_sync_interval = 4 hours sieve = file:~/sieve;active=~/.dovecot.sieve stats_refresh = 30 secs stats_track_cmds = yes } protocols = imap lmtp sieve recipient_delimiter = - service aggregator { fifo_listener replication-notify-fifo { mode = 0666 user = root } unix_listener replication-notify { mode = 0666 user = root } } service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } unix_listener auth-userdb { mode = 0777 } } service doveadm { inet_listener { address = 2400:8901:e001:3a::20 port = 4813 ssl = yes } user = root } service imap { executable = imap postlogin } service lmtp { inet_listener lmtp { address = ::1 port = 24 } unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0660 user = postfix } } service postlogin { executable = script-login -d rawlog } service replicator { process_min_avail = 1 unix_listener replicator-doveadm { mode = 0666 } } service stats { fifo_listener stats-mail { mode = 0666 } } ssl_ca = </etc/ssl/misc/alphassl_intermediate_ca.crt ssl_cert = </etc/ssl/dovecot/*.reub.net.crt ssl_cipher_list = DEFAULT:!EXPORT:!LOW:!MEDIUM:!MD5 ssl_client_ca_dir = /etc/ssl/certs ssl_client_ca_file = /etc/ssl/misc/alphassl_intermediate_ca.crt ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it ssl_protocols = !SSLv2 !SSLv3 !TLSv1 userdb { driver = passwd } protocol lmtp { mail_plugins = stats notify replication fts fts_lucene sieve ssl_dh = # hidden, use -P to show it } protocol !indexer-worker { ssl_dh = # hidden, use -P to show it } protocol lda { mail_plugins = stats notify replication fts fts_lucene sieve ssl_dh = # hidden, use -P to show it } protocol imap { mail_plugins = stats notify replication fts fts_lucene imap_stats ssl_dh = # hidden, use -P to show it } protocol sieve { ssl_dh = # hidden, use -P to show it } protocol pop3 { ssl_dh = # hidden, use -P to show it } And showing with -P as an example: protocol pop3 { ssl_dh = -----BEGIN DH PARAMETERS----- MIIBCAKCAQEAo4NpFI4fpUe65FVv1hotVS9pTUbCKs1ypGRZcFMXzpsXPqHU+M4s ... AAAAAAAAAAAAAAAAAAAAAAAAAAA= -----END DH PARAMETERS----- There is a single set of valid DH parameters for every protocol as listed above. It seems odd that ssl_dh is defined all of these protocols specifically too. This specific per-protocol definition of ssl_dh isn't specified in any config file. Reuben

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Replication to wrong mailbox
by Ralf Becker 02 Nov '17

02 Nov '17

It happened now twice that replication created folders and mails in the wrong mailbox :( Here's the architecture we use: - 2 Dovecot (2.2.32) backends in two different datacenters replicating via a VPN connection - Dovecot directors in both datacenters talks to both backends with vhost_count of 100 vs 1 for local vs remote backend - backends use proxy dict via a unix domain socket and socat to talk via tcp to a dict on a different server (kubernetes cluster) - backends have a local sqlite userdb for iteration (also containing home directories, as just iteration is not possible) - serving around 7000 mailboxes in a roughly 200 different domains Everything works as expected, until dict is not reachable eg. due to a server failure or a planed reboot of a node of the kubernetes cluster. In that situation it can happen that some requests are not answered, even with Kubernetes running multiple instances of the dict. I can only speculate what happens then: it seems the connection failure to the remote dict is not correctly handled and leads to situation in which last mailbox/home directory is used for the replication :( When it happened the first time we attributed it to the fact that the Sqlite database at that time contained no home directory information, which we fixed after. This first time (server failure) took a couple of minutes and lead to many mailboxes containing mostly folders but also some new arrived mails belonging to other mailboxes/users. We could only resolve that situation by rolling back to a zfs snapshot before the downtime. The second time was last Friday night during a (much shorter) reboot of a Kubernetes node and lead only to a single mailbox containing folders and mails of other mailboxes. That was verified by looking at timestamps of directories below $home/mdbox/mailboxes and files in $home/mdbox/storage. I can not tell if adding the home directory to the Sqlite database or the shorter time of the failure limited the wrong replication to a single mailbox. Can someone with more knowledge of the Dovecot code please check/verify how replication deals with failures in proxy dict. I'm of cause happy to provide more information of our configuration if needed. Here is an exert of our configuration (full doveconf -n is attached): passdb { args = /etc/dovecot/dovecot-dict-master-auth.conf driver = dict master = yes } passdb { args = /etc/dovecot/dovecot-dict-auth.conf driver = dict } userdb { driver = prefetch } userdb { args = /etc/dovecot/dovecot-dict-auth.conf driver = dict } userdb { args = /etc/dovecot/dovecot-sql.conf driver = sql } dovecot-dict-auth.conf: uri = proxy:/var/run/dovecot_auth_proxy/socket:backend password_key = passdb/%u/%w user_key = userdb/%u iterate_disable = yes dovecot-dict-master-auth.conf: uri = proxy:/var/run/dovecot_auth_proxy/socket:backend password_key = master/%{login_user}/%u/%w iterate_disable = yes dovecot-sql.conf: driver = sqlite connect = /etc/dovecot/users.sqlite user_query = SELECT home,NULL AS uid,NULL AS gid FROM users WHERE userid = '%n' AND domain = '%d' iterate_query = SELECT userid AS username, domain FROM users -- Ralf Becker EGroupware GmbH [www.egroupware.org] Handelsregister HRB Kaiserslautern 3587 Geschäftsführer Birgit und Ralf Becker Leibnizstr. 17, 67663 Kaiserslautern, Germany Telefon +49 631 31657-0

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