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[Dovecot] dovecot 2.1.5 performance
by Angel L. Mateo 21 Jun '12

21 Jun '12

Hello, I'm migrating from 1.1.16 running in 4 debian lenny servers virtualized with xenserver and 1 core and 5GB of RAM to 2.1.5 running in 4 ubuntu 12.04 servers with 6 cpu cores and 16GB of RAM virtualized with VMWare, but I'm having lots a performance problems. I don't think that virtualization platform could be the problem, because the new servers running in xenserver has the same problems than running in vmware. I have about 70000 user accounts, most of them without real activity (they are students who doesn't read his email or have its account redirected to other provider). I have about 700-1000 concurrent imap connections. I have storage in nfs (nfsv3, the nfs server is a celerra), but indexes are in local filesystems (each server has its own index fs). Mailboxes are in maildir format. Old servers and actual director servers are load balanced with an radware appdirector load balancer (the new backend servers don't need to be balanced because I'm using a director farm) In the old platform I have scenario number 2 described at http://wiki2.dovecot.org/NFS, but in the new ones I have a director proxy directing all connections from each user to the same server (I don't specify any server for the user, director selects it according to the hash algorithm it has). Some doubts I have for the recommended in that url: * mmap_disable: both single and multi server configurations have mmap_disable=yes but in index file section says that you need it if you have your index files stored in nfs. I have it stored locally. Do I need mmap_disable=yes? What it's the best? * dotlock_use_excl: it is set to no in both configurations, but the comment says that it is needed only in nfsv2. Since I have nfs3, I have it set it to yes. * mail_nfs_storage: In single server is set to no, but in multi server it set to yes. Since I have a director in front of my backend server, what is the recommended? With this configuration, when I have a few connections (about 300-400 imap connections) everything is working fine, but when I disconnect the old servers and direct all my users' connections to the new servers I have lot of errors. server loads increments to over 300 points, with a very high io wait. With atop, I could see that of my 6 cores, I have one with almost 100% waiting for i/o and the other with almost 100% idle, but load of the server is very, very high. With the old servers, I have performance problems, access to mail is slow, but it works. But with the new ones it doesn't work at all. Any idea? -- Angel L. Mateo Martínez Sección de Telemática Área de Tecnologías de la Información _o) y las Comunicaciones Aplicadas (ATICA) / \\ http://www.um.es/atica _(___V Tfo: 868887590 Fax: 868888337

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[Dovecot] public namespace
by Daniel Fischer 21 Jun '12

21 Jun '12

Hello, dovecot -n # 2.0.18: /etc/dovecot/dovecot.conf # OS: Linux 3.2.0-2-amd64 x86_64 Debian wheezy/sid mail_gid = 5000 mail_location = maildir:~:INDEX=/var/mail/indexes/%d/%n mail_privileged_group = vmail mail_uid = 5000 namespace { hidden = no inbox = yes list = yes location = prefix = separator = / subscriptions = yes type = private } namespace { list = children location = maildir:/var/mail/vhosts/%d/public:INDEX=/var/mail/indexes/%d/%n/public prefix = Public/ separator = / subscriptions = no type = public } i´m a little bit confused but I hope I find help here. The user mailboxes work perfectly just the public mailbox is a little bit tricky I expect that all public maildirs be placed under /var/mail/vhosts/%d/public. They are created by defining a public namespace, under which all the shared mailboxes are. For those special users, I have set the maillocation via passwd file to /%d/public/%n, all other users have /%d/%n. So we have following folder structure \public \public\.info \public\.lager \public\.buchhaltung And so on Thats works fine, but with subfolder start the problems. When the info-user loggs on and creates a subfolder under his INBOX(called hust2) then no other people can see this. Otherside, if a normal user creates a folder in public folder info(called hust), the info user can´ t see this one. If I look to filesystem, the reason is clear: %d/public/.info# ls -la insgesamt 32 drwx--S---+ 2 vmail vmail 6 Jun 19 11:50 cur -rwxrwx---+ 1 vmail vmail 51 Jun 21 09:50 dovecot-uidlist -rw-rw----+ 1 vmail vmail 8 Jun 19 11:51 dovecot-uidvalidity -r--r-----+ 1 vmail vmail 0 Jun 19 11:50 dovecot-uidvalidity.4fe04b06 drwx--S---+ 5 vmail vmail 78 Jun 19 11:54 .INBOX.hust2 drwx--S---+ 2 vmail vmail 6 Jun 19 11:50 new -rw-rw----+ 1 vmail vmail 18 Jun 19 11:51 subscriptions drwx--S---+ 2 vmail vmail 6 Jun 19 11:50 tmp drwx--S---+ 5 vmail vmail 78 Jun 21 09:51 .Trash %d/public# ls -la insgesamt 16 -rw-rw----+ 1 vmail vmail 8 Jun 19 11:51 dovecot-uidvalidity -r--r-----+ 1 vmail vmail 0 Jun 19 11:51 dovecot-uidvalidity.4fe04b36 drwx--S---+ 7 vmail vmail 4096 Jun 21 09:50 .info drwx--S---+ 5 vmail vmail 78 Jun 21 09:51 .info.hust A look to the info mailbox makes it clear: info@BLABLA \INBOX \hust2 >create by info user in his mailbox \Trash \Public \info >his own public share \hust >create by other user in public folder What I need is: %d/public/lager/cur %d/public/lager/new %d/public/lager/tmp %d/public/lager/.foo %d/public/lager/.foo.bar %d/public/ info /cur %d/public/ info /new %d/public/ info /tmp %d/public/info/.hust %d/public/info/.hust.deeperhust %d/public/info/.hust2 All public maildirs under /%d/public/%n Must I create a namespace for all public maildirs?: namespace { location = maildir:/var/mail/vhosts/%d/public/info } namespace { location = maildir:/var/mail/vhosts/%d/public/lager } I can´ t figure out on my own, please give me an explanation. Thanks for soon comment. Daniel

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[Dovecot] Dovecot not liking AD config from wiki??
by Kaya Saman 21 Jun '12

21 Jun '12

I think the issue seems to be the mechanism between Dovecot and AD, so basically PAM..... I adapted my pam.d file to this: # auth auth sufficient pam_krb5.so no_warn try_first_pass debug #auth sufficient pam_ssh.so no_warn try_first_pass auth required pam_unix.so no_warn try_first_pass # account #account required pam_nologin.so #account required pam_unix.so account required pam_krb5.so in the hope that this config would work: userdb { driver = static args = uid=501 gid=501 home=/mail/%u driver = static # args = uid=500 gid=500 home=/ZPOOL_1/%u # allow_all_users=yes } passdb { driver = pam } However I am still having issues :-( Regards, Kaya

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[Dovecot] migrating sql virtual 1 to 2, namespace configuration error: inbox=yes namespace missing
by Voytek Eymont 21 Jun '12

21 Jun '12

I'm trying to setup a new server on centos 6, from old dovecot 1.x I installed 'dovecot --version 2.1.1' from dovecot rpm I converted conf file as per migration specs, also, copied sql conf across when I try to retrieve email, log has *1: dovecot.conf -m *2 and sql conf *3 follows *1------------------------------- dovecot: master: Dovecot v2.1.1 starting up (core dumps disabled) dovecot: auth-worker(26890): mysql(127.0.0.1): Connected to database zzz dovecot: imap-login: Login: user=<name@tld>, method=PLAIN, rip=111.22.33.5, lip=111.22.33.4, mpid=26892, TLS dovecot: imap(name@tld): Error: user name@tld: Initialization failed: namespace configuration error: inbox=yes namespace missing dovecot: imap(name@tld): Error: Invalid user settings. Refer to server log for more information. *2----------------------------------- # doveconf -n # 2.1.1: /etc/dovecot/dovecot.conf # OS: Linux 2.6.32-220.17.1.el6.x86_64 x86_64 CentOS release 6.2 (Final) auth_cache_size = 1 k auth_mechanisms = plain login disable_plaintext_auth = no log_timestamp = "%Y-%m-%d %H:%M:%S " mail_location = maildir:~/Maildir mail_privileged_group = mail mbox_write_locks = fcntl namespace inbox { 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 = /etc/dovecot/dovecot-sql.conf driver = sql } protocols = imap pop3 service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } user = root } ssl = required ssl_cert = </etc/pki/dovecot/certs/dovecot.pem ssl_key = </etc/pki/dovecot/private/dovecot.pem userdb { driver = passwd } userdb { args = /etc/dovecot/dovecot-sql.conf driver = sql } protocol pop3 { pop3_uidl_format = %08Xu%08Xv } *3----------------------------------- cat dovecot-sql.conf driver = mysql connect = host=127.0.0.1 dbname=zzz user=yyy password=xxx user_query = SELECT concat('/var/mail/vhosts/', maildir) as home, concat('maildir:/var/mail/vhosts/', maildir) as mail, 5000 AS uid, 5000 AS gid, concat('maildir:storage=', quota) AS quota FROM mailbox WHERE username = '%u' AND active = '1' default_pass_scheme = MD5 user_query = SELECT '/var/mail/vhosts/%d/%n@%d' as home, 'maildir:/var/mail/vhosts/%d/%n@%d' as mail, 5000 AS uid, 5000 AS gid, concat('dirsize:storage=', quota) AS quota FROM mailbox WHERE username = '%u' AND active = '1' # Get the password password_query = SELECT username as user, password, '/var/mail/vhosts/%d/%n@%d' as userdb_home, 'maildir:/var/mail/vhosts/%d/%n@%d' as userdb_mail, 5000 as userdb_uid, 5000 as userdb_gid FROM mailbox WHERE username = '%u' AND active = '1' -- Voytek

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[Dovecot] troncated email
by Claude Gélinas 21 Jun '12

21 Jun '12

Hi, I'm on fc16 with dovecot and Claws Mail version 3.8.0 All email in INBOX are troncated as they arrive. I only get the title, from and date but no more core message could someone guide me so I find a solution for my problem. cannot lose my email Regards, Claude

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[Dovecot] Problem with Dovecot 2.0/2.1 and MySQL 5.1
by Mark Schmale 20 Jun '12

20 Jun '12

Hi everyone, since some time I got problems with dovecot & mysql. I got the problem with version 2.0.x and upgraded to 2.1.7 to check if its gone. But its not :( The logs just tell me this: dovecot: auth: Error: auth worker: Aborted request: Worker process died unexpectedly If I change to a sqlite setup, everything works fine. Here are some informations. I hope someone can tell me whats wrong with my system/setup. I really dont think that this is a bug because someone else should have hit that before me. doveconf - n # 2.1.7: /etc/dovecot/dovecot.conf # OS: Linux 3.2.2-hardened-r1 x86_64 Gentoo Base System release 2.1 auth_verbose = yes mail_location = maildir:~/%d/mail/%n 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 { 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 = /etc/dovecot/dovecot-sql.conf driver = sql } plugin { sieve = ~/.dovecot.sieve sieve_dir = ~/sieve } protocols = imap pop3 lmtp sieve service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0660 user = postfix } unix_listener auth-userdb { group = vmail user = vmail } } ssl_cert = </etc/ssl/dovecot/server.pem ssl_key = </etc/ssl/dovecot/server.key userdb { args = /etc/dovecot/dovecot-sql.conf driver = sql } protocol lda { mail_plugins = sieve } contents of dovecot-sql.conf: default_pass_scheme = PLAIN-MD5 driver = mysql connect = host=localhost dbname=config user=user password=pass password_query = SELECT CONCAT( u.username, '@', d.name ) AS user, password FROM mail_user AS u LEFT JOIN mail_domains AS d ON u.domain = d.id WHERE u.username = '%n' AND d.name = '%d' user_query = SELECT home, uid, gid FROM mail_user AS u LEFT JOIN mail_domains AS d ON u.domain = d.id WHERE u.username = '%n' AND d.name = '%d' // linebreaks added by mailclient for readability bt full with gdb: [Thread debx7fb891e85977 "216be49381eb03d180103cdf6eb90483" fields_count = 2 name = 0x0 #1 sql_query_callback (result=0x7fb891e82f60, sql_request=0x7fb891e82c08) at passdb-sql.c:87 auth_request = 0x7fb891e82a80 _module = <optimized out> module = <optimized out> passdb_result = PASSDB_RESULT_INTERNAL_FAILURE password = 0x0 scheme = <optimized out> ret = <optimized out> __FUNCTION__ = "sql_query_callback" #2 0x00007fb891c3c940 in driver_sqlpool_query_callback (result=0x7fb891e82f60, request=0x7fb891e82e50) at driver-sqlpool.c:635 db = 0x7fb891e66540 conn = 0x0 conndb = 0x7fb891e66910 #3 0x00007fb891c3dbe0 in driver_mysql_query (db=<optimized out>, query=<optimized out>, callback=0x7fb891c3c8c0 <driver_sqlpool_query_callback>, context=0x7fb891e82e50) at driver-mysql.c:296 result = 0x7fb891e82f60 #4 0x00007fb891c3cc41 in driver_sqlpool_query (_db=0x7fb891e66540, query=0x7fb891e561c8 "SELECT CONCAT( u.username, '@', d.name ) AS user, password FROM mail_user AS u LEFT JOIN mail_domains AS d ON u.domain = d.id WHERE u.username = 'masch' AND d.name = 'masch.it'", callback=0x7fb891c31960 <sql_query_callback>, context=0x7fb891e82c08) at driver-sqlpool.c:657 db = 0x7fb891e66540 request = 0x7fb891e82e50 conn = 0x7fb891e667c0 #5 0x00007fb891c23b49 in auth_worker_handle_passv (args=0x7fb891e560b8, id=1, client=<optimized out>) at auth-worker-client.c:200 auth_request = 0x7fb891e82a80 passdb = <optimized out> password = 0x7fb891e55ff2 "somepassword" passdb_id = 1 #6 auth_worker_handle_line (line=<optimized out>, client=<optimized out>) at auth-worker-client.c:559 args = out>0x7fb891e560a8 id = 1 ret = false #7 auth_worker_input (client=0x7fb891e80650) at auth-worker-client.c:647 _data_stack_cur_id = 3 line = <optimized out> ret = true #8 0x00007fb89179f4b6 in io_loop_call_io (io=0x7fb891e80970) at ioloop.c:379 ioloop = 0x7fb891e5e390 t_id = 2 #9 0x00007fb8917a043f in io_loop_handler_run (ioloop=<optimized out>) at ioloop-epoll.c:213 ctx = 0x7fb891e69100 events = <optimized out> event = 0x7fb891e69170 list = 0x7fb891e809c0 io = <optimized out> tv = {tv_sec = 59, tv_usec = 999508} msecs = <optimized out> ret = 1 i = <optimized out> j = <optimized out> call = <optimized out> #10 0x00007fb89179ed50 in io_loop_run (ioloop=0x7fb891e5e390) at ioloop.c:398 No locals. #11 0x00007fb891786a87 in master_service_run (service=0x7fb891e5e240, callback=<optimized out>) at master-service.c:544 No locals. #12 0x00007fb891c289a3 in main (argc=2, argv=0x7fb891e5e080) at main.c:373 c = <optimized out> best regards, Mark Schmale

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Re: [Dovecot] Dovecot Maildir - How to Seperate mail folders
by Guido Weiler 20 Jun '12

20 Jun '12

> Date: Mon, 18 Jun 2012 16:53:39 +0300 > From: Timo Sirainen <tss(a)iki.fi> > To: Dovecot Mailing List <dovecot(a)dovecot.org> > Subject: Re: [Dovecot] Dovecot Maildir - How to Seperate mail folders > Message-ID: <A828DCE4-9B1D-48AC-B1A1-C77C4D639AE4(a)iki.fi> > Content-Type: text/plain; charset=us-ascii > > On 18.6.2012, at 12.17, Guido Weiler wrote: > > > 01 OK Logged in. > >>> 02 list "" "*" > > * LIST (\HasNoChildren) "/" "INBOX" > > * LIST (\Noselect \HasChildren) "/" "greetings" > > * LIST (\HasNoChildren) "/" "greetings/INBOX" > > 02 OK List completed. > >>> 03 select "greetings/INBOX" > > 03 NO Mailbox doesn't exist: INBOX > >>> 04 select greetings > > 04 NO Mailbox doesn't exist: greetings > > > > --- > > > > What is this "\Noselect" mailbox showing up and why is it saying "greetings/INBOX" in the third row when in fact there > isn't a mailbox with this name? > > > > I am very sorry for having to bother you again, but I don't know what we are doing wrong here. > > (Dovecot version is 1.1.16) > > Fixed in newer versions, upgrade. > ------------------------------ Thank you. Can you tell me if this bug belongs to the LIST command only? Or is it generally impossible to SELECT such mailboxes with this version? Best Regards, Guido Weiler

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[Dovecot] Trouble with Trash
by Dominic Pratt 20 Jun '12

20 Jun '12

Hi guys and girls, Version: 2.0.19 - running on Ubuntu 12.04 LTS Server dovecot -n: # 2.0.19: /etc/dovecot/dovecot.conf # OS: Linux 3.3.1 x86_64 Ubuntu 12.04 LTS 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 ihave passdb { driver = pam } plugin { sieve = ~/.dovecot.sieve sieve_dir = ~/sieve } protocols = imap pop3 sieve service auth { unix_listener /var/spool/postfix/private/dovecot-auth { group = postfix mode = 0660 user = postfix } } ssl_cert = </etc/ssl/certs/dovecot.pem ssl_cipher_list = ALL:!LOW:!SSLv2:ALL:!aNULL:!ADH:!eNULL:!EXP:RC4+RSA:+HIGH:+MEDIUM ssl_key = </etc/ssl/private/dovecot.pem userdb { driver = passwd } protocol imap { imap_client_workarounds = delay-newmail mail_max_userip_connections = 10 } protocol pop3 { mail_max_userip_connections = 10 pop3_client_workarounds = outlook-no-nuls oe-ns-eoh } protocol lda { deliver_log_format = msgid=%m: %$ mail_plugins = sieve postmaster_address = postmaster quota_full_tempfail = yes rejection_reason = Your message to <%t> was automatically rejected:%n%r } My problem is, that actually old mails in the Thrash-Folder are deleted. This is crap, because I want to look at some mails again. I'm not sure if my Thunderbird does it or Dovecot. I don't think, TB does it, there's actually no option, I think. Any ideas? P.S.: Sorry for the bad english. -- "If you haven’t found it yet, keep looking. Don’t settle." Dominic Pratt Fachinformatiker Systemintegration Handy: +49 173 8371427

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[Dovecot] Dovecot not liking AD config from wiki??
by Kaya Saman 20 Jun '12

20 Jun '12

Hi, I'm trying to setup Dovecot with MS AD and am using this as my guide: http://wiki2.dovecot.org/HowTo/ActiveDirectoryNtlm I can definitely access information on the AD server using wbinfo -g and wbinfo -u..... Currently my dovecot.conf file looks like this: # v1.1: #auth_ntlm_use_winbind = yes # v1.2+: auth_use_winbind = yes auth_winbind_helper_path = /usr/local/bin/ntlm_auth protocols = imap # It's nice to have separate log files for Dovecot. You could do this # by changing syslog configuration also, but this is easier. log_path = /var/log/dovecot.log info_log_path = /var/log/dovecot-info.log # Disable SSL for now. ssl = no disable_plaintext_auth = no # We're using Maildir format #mail_location = maildir:~/Maildir mail_location = mbox:/mail:INBOX=/mail/%u # If you're using POP3, you'll need this: #pop3_uidl_format = %g # Authentication configuration: auth_verbose = yes auth_debug = yes auth_username_format = %n auth_mechanisms = plain ntlm login userdb { driver = static args = uid=501 gid=501 home=/mail/%u driver = static allow_all_users=yes } According to the documentation I should be using: userdb static { ... } which seems to be Dovecot v1. config, and additionally the "allow_all_users=yes" statement when added seems again v1. config since Dovecot 2. won't even start? In the meantime when not using "allow_all_users" Dovecot throws up these errors: Jun 20 11:30:40 master: Warning: Killed with signal 15 (by pid=4149 uid=0 code=kill) Jun 20 11:30:48 auth: Fatal: No passdbs specified in configuration file. LOGIN mechanism needs one Jun 20 11:30:48 master: Error: service(auth): command startup failed, throttling for 2 secs Jun 20 11:30:59 master: Warning: Killed with signal 15 (by pid=4182 uid=0 code=kill) Jun 20 11:31:13 auth: Fatal: No passdbs specified in configuration file. LOGIN mechanism needs one Jun 20 11:31:13 master: Error: service(auth): command startup failed, throttling for 2 secs Jun 20 11:32:38 master: Warning: Killed with signal 15 (by pid=4245 uid=0 code=kill) Jun 20 11:32:58 imap-login: Warning: Auth connection closed with 1 pending requests (max 0 secs, pid=4265, EOF) Jun 20 11:32:58 auth: Fatal: master: service(auth): child 4266 killed with signal 11 (core not dumped - set service auth { drop_priv_before_exec=yes }) -- this was after adding: passdb { driver = static } to the mix. I'm using Dovecot 2.1.3 on FreeBSD 8.2 RELEASE x64. Can anyone help me configuring Dovecot to authenticate? Regards, Kaya

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[Dovecot] Very High Load on Dovecot 2 and Errors in mail.err.
by Urban Loesch 20 Jun '12

20 Jun '12

Hi, I have a DELL PE R610 (32GB RAM 2x Six Core CPU and about 1,4 TB RAID 10) running with 20.000 Mailaccounts behind 2 Dovecot IMAP/POP3 Proxies on a Debian Lenny. The Server was running about 1 year without any problems. 15Min Load was between 0,5 and max 8. No high IOWAIT. CPU Idletime about 98%. But since yesterday morning the Systemload on the Server has been increased over 500. I Think this is very high. The strange thing: there was no IOWAIT and the CPU Idle time was allways the same on about 98%. The total amount of IMAP Sessions is about 300 - 600. Current vmstat and iostat: # vmstat 1 procs -----------memory---------- ---swap-- -----io---- -system-- ----cpu---- r b swpd free buff cache si so bi bo in cs us sy id wa 1 0 0 27040576 635460 3495600 0 0 14 15 2 31 0 0 99 0 0 0 0 27040320 635468 3496064 0 0 804 455 1383 1281 0 0 98 1 0 0 0 27047016 634964 3489312 0 0 216 156 1841 1292 1 0 98 1 0 0 0 27047140 635028 3489012 0 0 240 619 1629 1658 0 0 96 3 0 0 0 27047264 635120 3489172 0 0 92 0 1069 881 0 0 100 0 0 0 0 27047388 635120 3489256 0 0 0 46 1404 1265 0 0 100 0 0 0 0 27047512 635136 3489312 0 0 128 471 1539 1354 0 0 99 1 0 0 0 27047388 635156 3489384 0 0 12 360 1108 952 0 0 99 0 0 0 0 27047516 635160 3489408 0 0 104 12 893 677 0 0 99 0 ^C # iostat -k Linux 3.0.28-vs2.3.2.3-rol-em64t (mailstore4) 16.05.2012 _x86_64_ (24 CPU) avg-cpu: %user %nice %system %iowait %steal %idle 0,08 0,00 0,09 0,34 0,00 99,49 Device: tps kB_read/s kB_wrtn/s kB_read kB_wrtn sda 67,35 636,28 1080,48 31337690 53215361 dm-0 73,53 591,55 893,93 29134837 44027496 dm-1 15,06 42,40 181,79 2088493 8953661 drbd1 51,21 316,06 277,94 15566325 13689004 drbd0 9,22 23,50 80,38 1157641 3958796 Current Load: 08:55:44 up 14:04, 3 users, load average: 19,64, 14,47, 10,49 Load is increasing. The only strange thing I can see is this: # ps -ostat,pid,time,wchan='WCHAN-xxxxxxxxxxxxxxxxxxxx',cmd ax |grep D STAT PID TIME WCHAN-xxxxxxxxxxxxxxxxxxxx CMD D 18713 00:00:00 synchronize_srcu dovecot/imap D 18736 00:00:00 synchronize_srcu dovecot/imap D 18775 00:00:05 synchronize_srcu dovecot/imap D 20330 00:00:00 synchronize_srcu dovecot/imap D 20357 00:00:00 synchronize_srcu dovecot/imap D 20422 00:00:00 synchronize_srcu dovecot/imap D 20687 00:00:00 synchronize_srcu dovecot/imap S+ 20913 00:00:00 pipe_wait grep D There are many imap processes in D State. Amount is increasing. I think they are delayed and are wating for some event. I have no idea on which event they are waiting. And many of this in "mail.err" Log: May 16 08:52:11 dcot-rolmail-1.rolmail.net dovecot: master: Error: service(imap): Process 17468 is ignoring idle SIGINT May 16 08:52:24 dcot-rolmail-1.rolmail.net dovecot: master: Error: service(imap): Process 20307 is ignoring idle SIGINT May 16 08:52:25 dcot-rolmail-1.rolmail.net dovecot: master: Error: service(imap): Process 20318 is ignoring idle SIGINT May 16 08:52:26 dcot-rolmail-1.rolmail.net dovecot: master: Error: service(imap): Process 18964 is ignoring idle SIGINT May 16 08:52:28 dcot-rolmail-1.rolmail.net dovecot: master: Error: service(imap): Process 19244 is ignoring idle SIGINT May 16 08:54:22 dcot-rolmail-1.rolmail.net dovecot: master: Error: service(imap): Process 21177 is ignoring idle SIGINT May 16 08:54:41 dcot-rolmail-1.rolmail.net dovecot: master: Error: service(imap): Process 20647 is ignoring idle SIGINT May 16 08:55:10 dcot-rolmail-1.rolmail.net dovecot: master: Error: service(imap): Process 18836 is ignoring idle SIGINT May 16 08:55:17 dcot-rolmail-1.rolmail.net dovecot: master: Error: service(imap): Process 18857 is ignoring idle SIGINT May 16 08:55:19 dcot-rolmail-1.rolmail.net dovecot: master: Error: service(imap): Process 21176 is ignoring idle SIGINT May 16 08:55:24 dcot-rolmail-1.rolmail.net dovecot: master: Error: service(imap): Process 20688 is ignoring idle SIGINT May 16 08:55:25 dcot-rolmail-1.rolmail.net dovecot: master: Error: service(imap): Process 20973 is ignoring idle SIGINT May 16 08:56:44 dcot-rolmail-1.rolmail.net dovecot: master: Error: service(imap): Process 20326 is ignoring idle SIGINT Have you any Idea ho I can troubleshoot this problem? Some more technical information about the system: # uname -a Linux mailstore4 3.0.28-vs2.3.2.3-rol-em64t #1 SMP Thu May 3 09:31:08 CEST 2012 x86_64 GNU/Linux Dovecot Packages on Backend: installed: # dpkg -l |grep dovecot ii debian-dovecot-auto-keyring 2010.01.30 GnuPG archive keys of the Automatic Dovecot Debian repository ii dovecot-common 2:2.0.13-0~auto+54 secure mail server that supports mbox, maildir, dbox and mdbox mailboxes ii dovecot-imapd 2:2.0.13-0~auto+54 secure IMAP server that supports mbox, maildir, dbox and mdbox mailboxes ii dovecot-lmtpd 2:2.0.13-0~auto+54 secure LMTP server for Dovecot ii dovecot-managesieved 2:2.0.13-0~auto+54 secure ManageSieve server for Dovecot ii dovecot-mysql 2:2.0.13-0~auto+54 MySQL support for Dovecot ii dovecot-pop3d 2:2.0.13-0~auto+54 secure POP3 server that supports mbox, maildir, dbox and mdbox mailboxes ii dovecot-sieve 2:2.0.13-0~auto+54 sieve filters support for Dovecot Dovecot Packages on both Proxies installed: ii debian-dovecot-auto-keyring 2010.01.30 GnuPG archive keys of the Automatic Dovecot ii dovecot-common 2:2.0.17-0~auto+4 Transitional package for dovecot ii dovecot-core 2:2.0.17-0~auto+4 secure mail server that supports mbox, maild ii dovecot-gssapi 2:2.0.17-0~auto+4 GSSAPI authentication support for Dovecot ii dovecot-imapd 2:2.0.17-0~auto+4 secure IMAP server that supports mbox, maild ii dovecot-managesieved 2:2.0.17-0~auto+4 secure ManageSieve server for Dovecot ii dovecot-mysql 2:2.0.17-0~auto+4 MySQL support for Dovecot ii dovecot-pgsql 2:2.0.17-0~auto+4 PostgreSQL support for Dovecot ii dovecot-pop3d 2:2.0.17-0~auto+4 secure POP3 server that supports mbox, maild ii dovecot-sieve 2:2.0.17-0~auto+4 sieve filters support for Dovecot ii dovecot-sqlite 2:2.0.17-0~auto+4 SQLite support for Dovecot # doveconf -n # 2.0.13 (02d97fb66047): /etc/dovecot/dovecot.conf # OS: Linux 3.0.28-vs2.3.2.3-rol-em64t x86_64 Debian 6.0.2 ext4 auth_cache_negative_ttl = 0 auth_cache_size = 40 M auth_cache_ttl = 12 hours auth_mechanisms = plain login auth_username_format = %Lu auth_verbose = yes deliver_log_format = msgid=%m: %$ %p %w disable_plaintext_auth = no login_trusted_networks = 195.254.252.207 195.254.252.208 2a02:2e8:0:2:0:143:0:1 2a02:2e8:0:2:0:143:0:2 mail_gid = mailstore mail_location = mdbox:/home/vmail/%d/%n:INDEX=/home/dovecotindex/%d/%n mail_plugins = " quota zlib" mail_uid = mailstore 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 imapflags notify mdbox_rotate_size = 5 M passdb { args = /etc/dovecot/dovecot-sql-account.conf driver = sql } plugin { mail_log_events = delete undelete expunge copy mailbox_delete mailbox_rename mail_log_fields = uid box msgid size from mail_log_group_events = no quota = dict:Storage used::file:%h/dovecot-quota sieve = ~/.dovecot.sieve sieve_dir = ~/sieve sieve_extensions = +notify +imapflags sieve_max_redirects = 10 zlib_save = gz zlib_save_level = 5 } protocols = imap pop3 lmtp sieve service auth-worker { process_min_avail = 12 service_count = 0 vsz_limit = 512 M } service imap-login { inet_listener imap { port = 143 } process_min_avail = 12 service_count = 0 vsz_limit = 256 M } service imap { process_min_avail = 12 service_count = 0 vsz_limit = 512 M } service lmtp { inet_listener lmtp { address = * port = 24 } unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0666 user = postfix } vsz_limit = 512 M } service pop3-login { inet_listener pop3 { port = 110 } process_min_avail = 12 service_count = 0 vsz_limit = 256 M } service pop3 { service_count = 0 vsz_limit = 256 M } ssl = no ssl_cert = </etc/ssl/certs/dovecot.pem ssl_key = </etc/ssl/private/dovecot.pem userdb { args = /etc/dovecot/dovecot-sql-account.conf driver = sql } protocol lmtp { mail_plugins = " quota zlib sieve zlib" } protocol imap { imap_client_workarounds = tb-extra-mailbox-sep mail_max_userip_connections = 40 mail_plugins = " quota zlib imap_quota imap_zlib" } protocol pop3 { mail_plugins = " quota zlib" pop3_logout_format = bytes_sent=%o top=%t/%p, retr=%r/%b, del=%d/%m, size=%s uidl_hash=%u } Thanks and regards Urban Loesch

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