April 2012 - dovecot - dovecot.org

[Dovecot] Statistics scripts
by Timo Sirainen 08 Aug '12

08 Aug '12

I wrote two scripts, which you can use with the stats plugin enabled to get a better "doveadm stats top" than it currently is: http://dovecot.org/tools/stats-top.pl http://dovecot.org/tools/stats.pl

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[Dovecot] mysql auth failover failing
by Paul B. Henson 29 Jul '12

29 Jul '12

We are running dovecot to provide authentication for postfix, using two mysql servers in a multi-master replication set as the password source: ---------------------------------------- # 2.0.13: /etc/dovecot/dovecot.conf # OS: Linux 2.6.37-gentoo-r4 x86_64 Gentoo Base System release 2.0.2 auth_mechanisms = plain login digest-md5 cram-md5 auth_verbose = yes passdb { args = /etc/dovecot/dovecot-sql.conf driver = sql } protocols = none service auth-worker { unix_listener auth-worker { user = postfix } user = $default_internal_user } service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0660 user = postfix } user = postfix } ssl = no userdb { driver = passwd } --------------------------------------- With an sql config of: ------------------------- driver = mysql connect = host=mysql-1.unx.csupomona.edu host=mysql-2.unx.csupomona.edu dbname=idmgmt user=postfix password=XXXXXXX default_pass_scheme = PLAIN password_query = XXXXXXXXX ------------------------- According to the sample SQL configuration file "HA / round-robin load-balancing is supported by giving multiple host settings, like: host=sql1.host.org host=sql2.host.org". However, as far as I can tell dovecot only connects to the first listed host, and processes all queries through it, there does not appear to be any load-balancing going on. That's not necessarily a dealbreaker; however, high-availability does not appear to be working either. If I shutdown the first mysql server, dovecot starts to log connection failures: Sep 9 15:47:34 tweak dovecot: auth: Error: mysql(mysql-1.unx.csupomona.edu): Connect failed to database (idmgmt): Can't connect to MySQL server on 'mysql-1.unx.csupomona.edu' (111) - waiting for 1 seconds before retry Sep 9 15:47:39 tweak dovecot: auth: Error: mysql(mysql-1.unx.csupomona.edu): Connect failed to database (idmgmt): Can't connect to MySQL server on 'mysql-1.unx.csupomona.edu' (111) - waiting for 25 seconds before retry And postfix starts to fail authentications: Sep 9 15:47:35 tweak postfix/smtpd[5119]: warning: bender.iitsys.csupomona.edu[134.71.250.134]: SASL DIGEST-MD5 authentication failed: Connection lost to authentication server Now and again the authentication process dies: Sep 9 15:47:39 tweak dovecot: auth: Panic: file auth-request-handler.c: line 697 (auth_request_handler_flush_failures): assertion failed: (auth_request->state == AUTH_REQUEST_STATE_FINISHED) Sep 9 15:47:39 tweak dovecot: auth: Error: Raw backtrace: /usr/lib64/dovecot/libdovecot.so.0(+0x3f71a) [0x7f25822ca71a] -> /usr/lib64/dovecot/libdovecot.so.0(+0x3f766) [0x7f25822ca766] -> /usr/lib64/dovecot/libdovecot.so.0(+0x198ca) [0x7f25822a48ca] -> dovecot/auth() [0x4137f4] -> /usr/lib64/dovecot/libdovecot.so.0(io_loop_handle_timeouts+0xd4) [0x7f25822d5fe4] -> /usr/lib64/dovecot/libdovecot.so.0(io_loop_handler_run+0x5b) [0x7f25822d6bcb] -> /usr/lib64/dovecot/libdovecot.so.0(io_loop_run+0x28) [0x7f25822d5c48] -> /usr/lib64/dovecot/libdovecot.so.0(master_service_run+0x13) [0x7f25822c3de3] -> dovecot/auth(main+0x2be) [0x4179de] -> /lib64/libc.so.6(__libc_start_main+0xfd) [0x7f2581898bbd] -> dovecot/auth() [0x40bdc9] Sep 9 15:47:39 tweak dovecot: master: Error: service(auth): child 4154 killed with signal 6 (core dumps disabled) Requests start to pile up: Sep 9 15:51:46 tweak dovecot: auth: Warning: auth workers: Auth request was queued for 25 seconds, 45 left in queue Lookups time out: Sep 9 15:57:22 tweak dovecot: auth: Error: auth worker: Aborted request: Lookup timed out This occasionally pops up: Sep 9 15:58:38 tweak dovecot: auth: Fatal: net_connect_unix(auth-worker) failed: Resource temporarily unavailable And sometimes the auth process gets temporarily disabled: Sep 9 15:58:57 tweak dovecot: master: Error: service(auth): command startup failed, throttling Resulting in more postfix authentication failures: Sep 9 15:58:57 tweak postfix/smtpd[6531]: warning: bender.iitsys.csupomona.edu[134.71.250.134]: SASL DIGEST-MD5 authentication failed: Sep 9 15:59:08 tweak postfix/smtpd[6551]: fatal: no SASL authentication mechanisms To the point where postfix also temporarily throttles smtpd: Sep 9 15:59:21 tweak postfix/master[6526]: warning: /usr/lib64/postfix/smtpd: bad command startup -- throttling Resulting in a complete unavailability of smtp service, not just unavailability of authenticated services. I don't think all authentications fail during the scenario, but I think the majority do. Based on the network traffic, dovecot is almost continuously trying to connect to the first listed server. It sometimes connects to the second listed server, but when it does, the connection does not persist, it goes away almost immediately. Ideally, I would like no authentications to fail if one of the MySQL servers is unavailable. If a few fail just when the server dies, that would be undesirable but acceptable as long as they do not continuously fail while the server is down. Am I doing something wrong? Does the example sql config have incorrect information? We were previously running dovecot 1.2.11, we just recently upgraded to 2. In the previous version, we actually had two different passdb's configured, each one listing only one of the mysql servers. I seem to recall that was the recommendation at the time for high-availability. When that configuration did not seem to work under version 2, I found an updated recommendation to list both servers in the same passdb, which also does not appear to work correctly. I actually went back and tested the older version, and determined it seemed to work okay in the case where the server was up but the service was down, and connections were refused, but also failed a large number of authentication attempts when the server was completely down and connections were timing out. Thanks much... -- Paul B. Henson | (909) 979-6361 | http://www.csupomona.edu/~henson/ Operating Systems and Network Analyst | henson(a)csupomona.edu California State Polytechnic University | Pomona CA 91768

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[Dovecot] [PATCH] GSSAPI authorization and virtual users
by Sam Morris 02 Jul '12

02 Jul '12

The attached patch makes it possible for Kerberos principals to be associated with a password database entry by adding a new "k5principals" passdb setting. A client that successfully authenticates using GSSAPI will be able to log in as any user who has been associated with the client's Kerberos principal. This means that users can now use their Kerberos identities to access virtual mail accounts. The patch definitely needs review by someone familiar with Dovecot. It works for me on a small test installation using the passwd-file backend. Things that should probably be improved: 1. The list of authorized principals is stored in struct auth_request. I would prefer to store it in struct gssapi_auth_request, but auth-request.c does not know about structs that are specific to the different authentication plugins. This could be fixed in a more general way by adding a new function to struct mech_module to allow authplugins to read fields during passdb lookups. 2. The gssapi authplugin now does a credential lookup in order to trigger parsing of the k5principals setting. In order for this to work, auth_request_set_username is now called before mech_gssapi_userok. AFAICT the only impact of this is that messages logged by this function (and the functions it calls) will now use the name of the virtual account. 3. The credentials lookup triggers an info log message saying that credentials for GSSAPI were requested, "but we have only (e.g.) MD5-CRYPT". The authplugin doesn't actually want the credential, but I think that the only way the authplugin can trigger a passdb lookup is by requesting it. 4. The final part of the code in mech_gssapi_unwrap was moved to the callback that's triggered when the credentials lookup is complete. The code still needs access to the GSSAPI data, so the buffer pointer & length are now stored in struct gssapi_auth_request, making the inbuf parameter to the mech_gssapi_{sec_context,wrap,unwrap} functions superfluous. The parameters should be removed. 5. The k5principals list won't be processed on Solaris. The code added to the end of mech_gssapi_krb5_userok would have to be moved to a separate function and then be called from the Solaris code. 6. GCC tells me about assignment to incompatible pointer types in the code that iterates through gssapi_k5principals. I must be missing something. The patch is licensed under the MIT license. Please let me know what you think. -- Sam Morris <sam(a)robots.org.uk>

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[Dovecot] lmtp proxy timeout while waiting for reply to DATA reply
by Daniel Parthey 02 Jul '12

02 Jul '12

Hi, we are experiencing similar sporadic data timeout issues with dovecot 2.0.20 as in http://dovecot.org/pipermail/dovecot/2011-June/059807.html at least once a week. Some mails get temporarily deferred in the postfix queue since dovecot director lmtp refuses them and the mails are delivered at a later time. The problem applies to mails delivered to single users as well as distribution lists where the mails gets delivered to several mailboxes by postfix. The postfix log shows the following output: postfix.log.7.gz:Apr 21 18:48:46 10.129.3.233 postfix/lmtp[15868]: 88062C08E: to=<username(a)example.org>, orig_to=<username(a)example.org>, relay=127.0.0.1[127.0.0.1]:20024, delay=35, delays=5.4/0.01/0/30, dsn=4.4.0, status=deferred (host 127.0.0.1[127.0.0.1] said: 451 4.4.0 Remote server not answering (timeout while waiting for reply to DATA reply) (in reply to end of DATA command)) The dovecot.log (mailbox and director log there via syslog) shows the following output: Apr 21 18:46:53 10.129.3.233 dovecot: lmtp(15869): Debug: none: root=, index=, control=, inbox=, alt= Apr 21 18:46:53 10.129.3.233 dovecot: lmtp(15869): Connect from 127.0.0.1 Apr 21 18:46:53 10.129.3.233 dovecot: lmtp(15869): Debug: auth input: user=username(a)example.org proxy port=19024 host=10.129.3.190 proxy_refresh=450 Apr 21 18:46:53 10.129.3.233 dovecot: lmtp(15869): Disconnect from 127.0.0.1: Client quit (in reset) Apr 21 18:47:29 10.129.3.233 dovecot: lmtp(15869): Debug: none: root=, index=, control=, inbox=, alt= Apr 21 18:47:29 10.129.3.233 dovecot: lmtp(15869): Connect from 127.0.0.1 Apr 21 18:47:29 10.129.3.233 dovecot: lmtp(15869): Debug: auth input: user=username(a)example.org proxy port=19024 host=10.129.3.190 proxy_refresh=450 Apr 21 18:47:29 10.129.3.233 dovecot: lmtp(15869): Disconnect from 127.0.0.1: Client quit (in reset) Apr 21 18:48:15 10.129.3.233 dovecot: lmtp(15869): Debug: none: root=, index=, control=, inbox=, alt= Apr 21 18:48:15 10.129.3.233 dovecot: lmtp(15869): Connect from 127.0.0.1 Apr 21 18:48:15 10.129.3.233 dovecot: lmtp(15869): Debug: auth input: user=username(a)example.org proxy port=19024 host=10.129.3.190 proxy_refresh=450 Apr 21 18:48:46 10.129.3.233 dovecot: lmtp(15869): Disconnect from 127.0.0.1: Client quit (in reset) One cannot identify the lmtp log origin from the log_format prefixes, but it seems that the "lmtp($PID)" log originated from the director, since proxy port 19024 is mentioned in the logs, which is our dovecot mailbox backend. Config for dovecot (mailbox) and director (proxy) is attached. mail_debug is yes for both dovecot and director. How can we find out more information? Shall I apply the following patches from http://dovecot.org/pipermail/dovecot/2011-June/059987.html or are they already included with version 2.0.20? Regards, Daniel

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[Dovecot] permissions on auth-userdb
by spamvoll＠googlemail.com 28 Jun '12

28 Jun '12

Hi.. im still trying to upgrade to 2.0. Im getting: dovecot: lda: Error: userdb lookup: connect(/var/run/dovecot/auth-userdb) failed: Permission denied (euid=10000(vmail) egid=10000(vmail) missing +r perm: /var/run/dovecot/auth-userdb, euid is not dir owner) the error is correct caus its owned by root. My Questions is who should own it ? Im not sure how that works, what process/user calls the auth-userdb ? The auth-userdb returns the args generated in master.conf, right ? i think comment out the user and group setting in master.conf will fix it but im not sure if that is the securest way. the mails come from postfix via dovecot-lda Hans master.conf service auth { # auth_socket_path points to this userdb socket by default. It's typically # used by dovecot-lda, doveadm, possibly imap process, etc. Its default # permissions make it readable only by root, but you may need to relax these # permissions. Users that have access to this socket are able to get a list # of all usernames and get results of everyone's userdb lookups. unix_listener auth-userdb { mode = 0600 #user = vmail #group = vmail } auth-ldap.conf.ext passdb { driver = ldap args = /etc/dovecot/dovecot-ldap.conf.ext } userdb { driver = static args = uid=vmail gid=vmail home=/home/MAILBOXES/%u/ mail=/home/MAILBOXES/%u/mail }

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[Dovecot] gnutls support
by Daniel L. Miller 12 Jun '12

12 Jun '12

Other than license issues, is there an advantage to using gnutls vs openssl? Or is openssl superior - at least in the current implementations? -- Daniel

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[Dovecot] 2.0.X -> 2.1 pitfalls?
by Frank Elsner 09 Jun '12

09 Jun '12

Hi all, are there any pitfalls known for the migration from 2.0.18 to 2.1? Can I simply stop dovecot, make install and start again? --Frank Elsner

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[Dovecot] stats + fts squat plugins, indexer-worker error on message indexing
by David Warden 16 May '12

16 May '12

On RHEL 6.2 + dovecot 2.1.5 with the stats and fts (squat) plugins enabled and each user having their own uid on the system I get the following error in the logs when the indexer-worker process indexes some messages: Apr 25 09:56:19 wardentest3 dovecot: imap-login: Login: user=warden, method=PLAIN, rip=137.238.60.164, lip=137.238.2.240, lport=1993, mpid=19464, encryption=TLS Apr 25 09:56:26 wardentest3 dovecot: service=indexer-worker user=warden rip= Indexed 12 messages in INBOX Apr 25 09:56:26 wardentest3 dovecot: service=indexer-worker user=warden rip= Error: open(/proc/self/io) failed: Permission denied Apr 25 09:56:29 wardentest3 dovecot: service=imap user=warden rip=137.238.60.164 Disconnected: Logged out bytes(in/out)=46/780 What I did to generate the above was remove the squat indexes for my Inbox then log in via telnet and search for a string in my Inbox, which forced an index of the messages in my Inbox. Based on http://wiki2.dovecot.org/Services#indexer-worker it seems like this is because the indexer-worker process is created as root but at the time of indexing the indexer-worker drops privs to the mail user. In /proc/<indexer-worker pid>/, io is mode 0400 and owned by root, so it makes sense that the mail user would be unable to read that file. The strange thing is it looks like the stats are still collected (unless I am reading the output of the stats dump incorrectly): [root@wardentest3 mailtest]# doveadm stats dump -s /var/run/dovecot/mailtest/stats command user=warden cmd args session user last_update user_cpu sys_cpu min_faults maj_faults vol_cs invol_cs disk_input disk_output read_count read_bytes write_count write_bytes mail_lookup_path mail_lookup_attr mail_read_count mail_read_bytes mail_cache_hits select inbox 27fb87218302984f084c0000ae899e04 warden 1335362182.950250 0.000000 0.000000 172 0 46 0 0 12288 13 7883 4 381 0 0 0 0 0 search text "warden" 27fb87218302984f084c0000ae899e04 warden 1335362186.588023 0.001000 0.000000 32 0 4 1 0 0 4 108 1 43 0 0 0 0 0 logout 27fb87218302984f084c0000ae899e04 warden 1335362189.161790 0.000000 0.000000 1 0 0 3 0 0 1 108 3 157 0 0 0 0 0 This obviously isn't a show-stopper but if this is causing stats to be incorrect it would be great if this could be fixed. -David Warden My doveconf -n: # 2.1.5: /etc/dovecot/mailtest/dovecot.conf doveconf: Warning: service auth { client_limit=4096 } is lower than required under max. load (12288) doveconf: Warning: service anvil { client_limit=4096 } is lower than required under max. load (12291) # OS: Linux 2.6.32-220.7.1.el6.x86_64 x86_64 Red Hat Enterprise Linux Server release 6.2 (Santiago) nfs auth_cache_negative_ttl = 0 auth_cache_size = 16 M auth_gssapi_hostname = $ALL auth_krb5_keytab = /etc/dovecot/mailtest.combined.keytab auth_master_user_separator = * auth_mechanisms = plain login gssapi auth_username_format = %Ln base_dir = /var/run/dovecot/mailtest/ default_client_limit = 4096 default_process_limit = 4096 deliver_log_format = msgid="%m" subject="%s" from="%f" size=%p result="%$" first_valid_uid = 0 hostname = mailtest.geneseo.edu instance_name = mailtest lda_mailbox_autocreate = yes lda_mailbox_autosubscribe = yes login_log_format_elements = user=%u method=%m rip=%r lip=%l lport=%a mpid=%e encryption=%c mail_fsync = always mail_location = maildir:/Mail/mailhome/%Ln/mailtest/Maildir:CONTROL=/Mail/mailhome/%Ln/mailtest/.dovecot-control:INDEX=/Mail/mailhome/%Ln/mailtest/.dovecot-index mail_log_prefix = "service=%s user=%u rip=%r " mail_nfs_index = yes mail_nfs_storage = yes mail_plugins = zlib quota mail_log notify fts fts_squat stats maildir_very_dirty_syncs = yes 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 mbox_write_locks = fcntl mmap_disable = yes namespace default { inbox = yes location = mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox Junk { auto = no special_use = \Junk } mailbox Sent { auto = subscribe special_use = \Sent } mailbox Trash { auto = subscribe special_use = \Trash } prefix = separator = . type = private } passdb { args = /etc/dovecot/passwd.masterusers driver = passwd-file master = yes } passdb { args = cache_key=%u dovecot driver = pam } plugin { fts = squat mail_log_events = delete undelete expunge copy mailbox_delete mailbox_rename flag_change append mail_log_fields = uid box msgid size from subject flags mail_log_group_events = yes quota = maildir:User quota quota_exceeded_message = Quota exceeded (mailbox for user is full). Please see http://go.geneseo.edu/emailoverquota for help deleting messages while over quota. quota_rule = *:storage=200M quota_rule2 = Trash:storage=+50M sieve = /Mail/mailhome/%Ln/mailtest/.filter.sieve sieve_dir = /Mail/mailhome/%Ln/mailtest/.sievedir sieve_max_redirects = 25 stats_memory_limit = 32 M stats_refresh = 30 secs stats_track_cmds = yes } postmaster_address = postmaster(a)geneseo.edu protocols = imap sieve lmtp quota_full_tempfail = yes service auth { unix_listener auth-exim { group = exim mode = 0660 } } service imap-login { inet_listener imap { port = 1143 } inet_listener imaps { port = 1993 } service_count = 0 vsz_limit = 256 M } service imap { process_limit = 4096 } service lmtp { inet_listener lmtp { port = 124 } } service managesieve-login { inet_listener sieve { port = 14190 } inet_listener sieve_deprecated { port = 12000 } } service pop3 { process_limit = 4096 } service stats { fifo_listener stats-mail { mode = 0666 } } ssl_ca = </etc/pki/tls/certs/geotrust-intermediate.pem ssl_cert = </etc/pki/tls/certs/wildcard-geotrust.geneseo.edu.pem ssl_key = </etc/pki/tls/private/wildcard-geotrust.geneseo.edu.key userdb { driver = passwd } verbose_proctitle = yes protocol lmtp { mail_plugins = zlib quota mail_log notify fts fts_squat stats sieve } protocol lda { mail_location = maildir:/Mail/mailhome/%Ln/mailtest/Maildir:CONTROL=/Mail/mailhome/%Ln/mailtest/.dovecot-control:INDEX=/Mail/mailhome/%Ln/mailtest/.dovecot-index mail_plugins = zlib quota mail_log notify fts fts_squat stats sieve plugin { quota = maildir:User quota quota_rule = *:storage=200M quota_rule2 = Trash:storage=+50M zlib_save = gz zlib_save_level = 6 } } protocol imap { imap_logout_format = bytes(in/out)=%i/%o mail_max_userip_connections = 50 mail_plugins = zlib quota mail_log notify fts fts_squat stats imap_quota autocreate imap_zlib imap_stats } protocol sieve { managesieve_logout_format = bytes(in/out)=%i/%o } protocol pop3 { pop3_client_workarounds = outlook-no-nuls oe-ns-eoh pop3_logout_format = bytes(in/out)=%i/%o, top=%t/%p, retr=%r/%b, del=%d/%m, mailbox-size=%s pop3_uidl_format = UID%u-%v } remote 137.238.0.0/16/16 { disable_plaintext_auth = no }

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[Dovecot] default mail quota when using per user quota
by Andreas Helmcke 14 May '12

14 May '12

Hello, using dovecot 2.1 and per user mail quota via ldap is there a way to have a default quota which gets used, if the "quota" field in ldap is not set? I tried with: plugin { quota = maildir:User quota quota_rule = *:storage=3G } userdb { args = /etc/dovecot/dovecot-ldap.conf driver = ldap } and in dovecot-ldap.conf: user_attrs = dcMailQuota=quota_rule=*:storage=%$ but with this configuration the mail quota /allways/ gets loaded from ldap resulting in users without dcMailQuota attribute having no quota at all. Greetings Andreas

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[Dovecot] dovecot and systemd
by Michal Hlavinka 09 May '12

09 May '12

Hi all, dovecot supports systemd socket activation. Together with standard unit activation (like old sysv init script), there are two ways how to configure dovecot(only interface:port, not whole configuration). This can result in situation where those configurations does not say the same. Question is what should happen then? For example, lets have dovecot configured to listen for imap(s) and lets have systemd dovecot socket configured to listen for all protocols - pop3(s) and imap(s). When dovecot is configured to start on boot, systemd will start it and dovecot will listen on imap(s) ports. But when dovecot.socket is enabled, it'll listen on pop3(s) too and when new pop3 connection comes, it'll pass it to dovecot and dovecot will serve it. The question is: Should this happen? What exactly should happen when dovecot.conf does not match dovecot.socket configuration? Michal

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