- dovecot - dovecot.org

vsz_limit of service doveadm "ignored"?
by Philipp 08 Jul '15

08 Jul '15

Hello, dovecot 2.2.18 on CentOS6.5 Jul 08 11:53:44 dsync-server(system): Fatal: master: service(doveadm): child 32554 returned error 83 (Out of memory (service doveadm { vsz_limit=521 MB }, you may need to increase it) - set CORE_OUTOFMEM=1 environment to get core dump) I tried increasing to 1 G, 1024 M or even disabling via value of zero -- to no change. Every other service has the famous 18446744073709551615 B limit. default_vsz_limit = 2 G The second node with the same setup/config is happily accepting a higher value, since both come from the same provisioning I cannot see (or expect) differences around ulimit and thelike. The configuration comes from a single file, so no include drama or such. Any pointers why the setting is being ignored?

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ESEARCH multiple folders
by Peter Chiochetti 08 Jul '15

08 Jul '15

FTS-Solr is blazingly fast; yet searching e.g. an archive with subfolders still is slow; I learned, that this is a feature/bug of the imap protocol. So I'd like to ask: Does or will dovecot support the "IMAP4 Multimailbox SEARCH Extension" specified in RFC 7377? -- Kind regards Peter

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Scalability with high density servers and proxies, TCP port limits
by Christian Balzer 08 Jul '15

08 Jul '15

Hello, first post in 3 years, kinda shows how painless Dovecot is. ^o^ Also this isn't really a dovecot issue, alas it's involved and since there are some large scale implementations of it I hope somebody here has some insights I might have missed. Currently we're running this setup: 1. LVS (DR mode) in a HA configuration (2 node cluster) 2. Dovecot in proxy mode on a 2 node cluster 3. Dovecot on actual mailbox servers (dual node DRBD clusters) There are about 500k users, but most of them use POP3, so there are usually less than 6k IMAP sesions at any given time. This is about to change, I'm looking at potentially millions of users who will have all semi-permanent IMAP sessions. We already have a pure SSD based mailbox cluster and based on the experiences with that another one is on order that will be able to easily handle about 500k users with regards to IOPS and other needs. However there's the issue of having all these concurrent IMAP sessions. Namely, running out of ephemeral ports. Lets assume 2 million users and 50k ports per IP and revisit the setup above. 1. LVS should have no problem, from experience and tests I expect a well tuned and spec'ed machine to handle millions of connections. This is in DR mode, in NAT mode I assume things would run into a wall a lot quicker. But even if LVS should run out of steam, there's a wide selection of high capacity load balancers available. 2. Here is where the fun starts. Each IMAP session that gets proxied to the real mailbox server needs a port for the outgoing connection. So to support 2 million sessions we need 40 IP addresses here. Ouch. And from a brief test having multiple IP addresses per server won't help either (Dovecot unsurprisingly picks the main IP when establishing a proxy session to the real mailbox), at least not with just one default GW. 3. All of this gets repeated on the actual mailbox servers, by either having a lot of low density servers or (preferably) high density servers with multiple IP addresses. Am I on track so far or missing something obvious? How many concurrent connections do you (hello Timo) think dovecot in proxy mode can handle? High performance mode of course in this case. I'm interested in internal limitations, assume that CPU and RAM are amply supplied. Any and all feedback is appreciated. Regards, Christian -- Christian Balzer Network/Systems Engineer chibi(a)gol.com Global OnLine Japan/Fusion Communications http://www.gol.com/

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HELP: wrinting dovecot-sql.conf to authenticate to an existing database
by Filippo Zeus 08 Jul '15

08 Jul '15

hi all, can anyone help me with dovecot-sql.conf please ? I'm not a mysql expert and I'am trying to authenticate dovecot2 to an existing database. I have a database "egroupware" with table "egw_accounts". The field "account_lid" is the full email address and "account_pwd" is the password in Blowfish format. Here is my dovecot-sql.conf driver = mysql connect = host=localhost dbname=egroupware user=egroupware password=********* default_pass_scheme = BLF-CRYPT password_query = SELECT account_pwd AS password FROM egw_accounts WHERE account_lid = '%u' when I try to login to POP or IMAP I got this error in mail.log/mail.info Error: sql(hidden@mydomain.com,::1): Invalid password in passdb: crypt() failed: Invalid argument auth: Debug: client passdb out: FAIL#0111#011user=hidden(a)mydomain.com dovecot: pop3-login: Debug: Ignoring unknown passdb extra field: I think I'm having trouble with the password value that is stored in the account_pwd as: {crypt}$2a$12$XTAolzXgwMC211MuZELQUedPv9tjZNs7Osh97PnZ50pAKuk3WPGmS Reading at http://wiki2.dovecot.org/Authentication/PasswordSchemes I suppose that the heading "{crypt}$2a$" instead of a simple "$2a$" (witch identifies a Blowfish password) is my problem. How can I fix this ? Here is my dovecot -n output: # 2.2.13: /etc/dovecot/dovecot.conf # OS: Linux 3.16.0-4-amd64 x86_64 Debian 8.1 xfs auth_cache_size = 64 M auth_debug = yes auth_mechanisms = plain login lda_mailbox_autocreate = yes log_timestamp = "%Y-%m-%d %H:%M:%S " login_log_format_elements = USER=<%u> METHOD=%m FROM=%r TO=%l %c mail_location = maildir:/var/mail/%d/%n/Maildir mail_plugins = quota mail_privileged_group = 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 spamtest spamtestplus imapflags notify namespace inbox { inbox = yes location = mailbox Archive { auto = no special_use = \Archive } mailbox "Deleted Messages" { auto = no special_use = \Trash } mailbox Drafts { special_use = \Drafts } mailbox Sent { special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Spam { auto = no special_use = \Junk } mailbox Trash { auto = no special_use = \Trash } prefix = separator = . } passdb { args = /etc/dovecot/dovecot-sql.conf.ext driver = sql } plugin { quota = maildir:User quota quota_exceeded_message = Storage quota for this account has been exceeded, please try again later. quota_grace = 10%% quota_rule = *:storage=6G quota_rule2 = Trash:storage=+100M quota_rule3 = spam:ignore quota_warning = storage=95%% quota-warning 95 %u sieve = ~/dovecot.sieve sieve_before = /var/mail/sieve/before.sieve sieve_default = /var/mail/sieve/default.sieve sieve_dir = ~/sieve.d sieve_extensions = +notify +imapflags +spamtest +spamtestplus +relational +comparator-i;ascii-numeric sieve_global_dir = /var/mail/sieve/global.d sieve_max_script_size = 1M } postmaster_address = postmaster@%d protocols = " imap sieve pop3 sieve" service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } } service imap-login { inet_listener imap { port = 143 } inet_listener imaps { port = 993 ssl = yes } } service managesieve-login { inet_listener sieve { port = 4190 } service_count = 1 vsz_limit = 64 M } service managesieve { process_limit = 15 } service quota-warning { executable = script /usr/local/bin/quota-warning.sh unix_listener quota-warning { user = vmail } user = dovecot } ssl = required ssl_cert = </etc/ssl/dharma/mail/mail_antonica_it.crt ssl_key = </etc/ssl/dharma/mail/mail_antonica_it.key userdb { args = uid=vmail gid=vmail home=/var/mail/%d/%n driver = static } protocol lda { mail_plugins = quota sieve } protocol imap { mail_plugins = quota imap_quota } protocol sieve { mail_max_userip_connections = 10 managesieve_logout_format = bytes=%i/%o managesieve_max_line_length = 65536 }

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Autocreate folders with specific permissions
by Fabio S. Schmidt 07 Jul '15

07 Jul '15

Hi, I have Dovecot 2.1 deployed running about 65k mailboxes. We need to create a specific folder for all users with specific permissions. I mean, the user could not delete or rename the folder. To create the folder automatically I have used the autocreate, but is there any way to set specific permissions on those folders? My best regards.

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Problem with IMAP-Proxy and M$ Exchange-Server
by Luca Bertoncello 07 Jul '15

07 Jul '15

Hi List! I **HATE** Exchange-Server. I think it's not able to manage E-Mails, but we have to use it at work... Well, we need to read the E-Mails from outside, so I configured Dovecot with IMAPC to connect to the Exchange-Server. It works, but I have a problem... If I receive an E-Mail, and I read it from my phone (for example), I see in Outlook that the E-Mail as been read. If I move the E-Mail in another folder from my phone, I see in Outlook the E-Mail in the new folder **AND** in the INBOX. If I check my E-Mail from another phone (or Mail-Client), I see the E-Mail just in the new folder, so I think, the Exchange-Server did move it. But Outlook does not get this information... Any idea how can I solve my problem? Thanks Luca Bertoncello (lucabert(a)lucabert.de)

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Large jumps in dovecot-uidlist
by Mark 07 Jul '15

07 Jul '15

Since upgrading to Debian Wheezy I have been observing large jumps in the value stored in dovecot-uidlist. The effect of these jumps is to confuse some mail clients (Thunderbird, Opera Mail) causing them not to display messages from a (random?) point in time onwards in the affected folder. I have been unable to determine the root cause of these jumps. What I do know: 1. I never observed the problem while running Debian Squeeze. 2. The only way I have found to fix the issue is to remove all the dovecot* files from the affected folder and restart dovecot. I have tried removing various subsets of the dovecot* files but haven't yet found a subset that works. 3. I first tried upgrading from Squeeze to Wheezy within a few weeks of the Wheezy release. At that point the problem occurred so frequently that I couldn't sync my mail client with my mail box. Multiple folders exhibited this problem and while I was fixing them the problem appeared in other folders. I was unable to reach a point where the system was stable so I reverted back to Squeeze. 4. Some time later (I think a year but I am not sure) I tried the upgrade to Wheezy again. This time the system was stable. After a few days I noticed that the problem was still occurring but less frequently. Since then I have been fixing the problem as I notice it and experimenting with various settings (mainly locking related) without success. I now have a cron job that looks for problematic folders and fixes them when found. 5. I have updated Dovecot packages to those from Jessie via wheezy-backports and the problem still occurs. 6. Dovecot is installed along with postfix, amavisd-new, clamav-daemon, procmail and fetchmail. 7. The mail server is running on a eSATA SheevaPlug that boots of an external USB drive. All user home dirs (and associated mailboxes) are located on a LUKS/ext3 encrypted partition. 8. The output of dovecot -n may be found at the end of this mail. 9. Uid values for the three most recent instances of this problem are: 3801596527, 3371927249, 3443181615 10. Some folders seem more susceptible to this problem but I have not been able to identify any common factors/triggers. 11. The problem occurs - on average - once a day. I am happy to provide any further information, configure any debug logging and/or test suggested configuration settings that may help track down the root cause of this problem. Any help gratefully appreciated. Mark # 2.2.13: /etc/dovecot/dovecot.conf # OS: Linux 3.2.0-4-kirkwood armv5tel Debian 7.8 mail_debug = yes mail_location = maildir:~/Maildir mail_max_userip_connections = 100 namespace { inbox = yes location = mailbox { special_use = \Drafts name = Drafts } mailbox { special_use = \Junk name = Junk } mailbox { special_use = \Sent name = Sent } mailbox { special_use = \Sent name = Sent Messages } mailbox { special_use = \Trash name = Trash } prefix = name = inbox } passdb { driver = pam } protocols = " imap" service replication-notify-fifo { name = aggregator } service anvil-auth-penalty { name = anvil } service auth-worker { name = auth-worker } service { unix_listener { group = postfix mode = 0666 user = postfix path = /var/spool/postfix/private/auth-client } name = auth } service config { name = config } service dict { name = dict } service login/proxy-notify { name = director } service dns-client { name = dns_client } service doveadm-server { name = doveadm } service { inet_listener { port = 0 name = imap } inet_listener { port = 993 ssl = yes name = imaps } process_min_avail = 5 name = imap-login } service imap-urlauth { name = imap-urlauth-login } service imap-urlauth-worker { name = imap-urlauth-worker } service token-login/imap-urlauth { name = imap-urlauth } service { executable = imap postlogin name = imap } service indexer-worker { name = indexer-worker } service indexer { name = indexer } service ipc { name = ipc } service lmtp { name = lmtp } service log-errors { name = log } service pop3 { name = pop3-login } service login/pop3 { name = pop3 } service { executable = script-login -d rawlog name = postlogin } service replicator-doveadm { name = replicator } service login/ssl-params { name = ssl-params } service stats-mail { name = stats } ssl_cert = </etc/ssl/certs/smtpd.crt ssl_cipher_list = HIGH:MEDIUM:!aNULL:!MD5:!RC4 ssl_key = </etc/ssl/private/smtpd.key userdb { driver = passwd } protocol imap { service replication-notify-fifo { name = aggregator } service anvil-auth-penalty { name = anvil } service auth-worker { name = auth-worker } service auth-client { name = auth } service config { name = config } service dict { name = dict } service login/proxy-notify { name = director } service dns-client { name = dns_client } service doveadm-server { name = doveadm } service imap { name = imap-login } service imap-urlauth { name = imap-urlauth-login } service imap-urlauth-worker { name = imap-urlauth-worker } service token-login/imap-urlauth { name = imap-urlauth } service login/imap { name = imap } service indexer-worker { name = indexer-worker } service indexer { name = indexer } service ipc { name = ipc } service lmtp { name = lmtp } service log-errors { name = log } service pop3 { name = pop3-login } service login/pop3 { name = pop3 } service replicator-doveadm { name = replicator } service login/ssl-params { name = ssl-params } service stats-mail { name = stats } }

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Are the Dovecot Enterprise Edition Ubuntu 14.04 packages stable?
by deoren 07 Jul '15

07 Jul '15

I recently begun to migrate mail services to a new box so I could retrofit an existing box. I took this opportunity to check back on the official Dovecot Enterprise Edition (EE) pages to see if support has been added for Ubuntu 14.04 LTS. I never could find the information on the dovecot.fi website, but taking my existing credentials for Dovecot EE repo access and looking at the root path I see that 14.04 packages are available from the APT repo. Are those stable or experimental? I have an Ubuntu 12.04 box I've kept around just for Dovecot EE that I'd like to move to 14.04 if the packages are stable. p.s. Thank you for continuing to provide access for existing users of the repo, but what would new users need to do to obtain access? Thanks for your time.

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Dovecot - Config file details
by Sachin Kulkarni1 07 Jul '15

07 Jul '15

Hello All, We want to install / configure and test Dovecot. We are doing it for the first time. After installation we are now looking for configuration file and need to know significance of below params and what values we should provide ? protocols = listen = base_dir = login_greeting = Please help. Thanks and Regards, Sachin Kulkarni ============================================================================================================================ Disclaimer: This message and the information contained herein is proprietary and confidential and subject to the Tech Mahindra policy statement, you may review the policy at http://www.techmahindra.com/Disclaimer.html externally http://tim.techmahindra.com/tim/disclaimer.html internally within TechMahindra. ============================================================================================================================

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Questions about hardlinks, alternate storage and compression
by Gionatan Danti 06 Jul '15

06 Jul '15

Hi all, I have some questions about hardlinks, alternate storage and compression. I already scanned the list for related information and I have an idea of how things works, but I would like to have a definite answer. System spec: - CentOS 6.6 x64 - dovecot-2.0.9-8.el6_6.4.x86_64 RPM package/version - sdbox mail store 1) About hardlinks: when sending the same message to two different recipients, I see that the two u.x files are created as two different files. Diffing them, I see that the only difference is a single char (see [1] for an example). My questions are: a) it is possible to tell dovecot to create a single file + a single hardlink (linkref=2)? As other IMAP servers support that features (eg: Cyrus, CommunigatePro, etc) I am wondering if I missed something in configuring dovecot... b) If it is not possible, can I run a script that compare the various files and substitute equal ones (minus the changing line) with hardlinks, or it will confuse dovecot? As a side note, why the changing line ever exists? 2) About alternate storage and compression: actually, I use a single mail_location without compression. I would like to have an alternate storage and to enable compression on it only, leaving the main location without compression. I if understand it correctly, it _should_ be done using a command similar to "doveadm -Dv -o "plugin/zlib_save=gz" altmove -uu testuser sentbefore 8d". I'm right thinking that it should work? I will really end with a primary uncompressed mail store and an alternate, zlib-compressed one? Thank you all and sorry if I did some naive questions. [1] 63c63 < G2fd0811c64be8e553d970000eaa8309f --- > G2ed0811c64be8e553d970000eaa8309f -- Danti Gionatan Supporto Tecnico Assyoma S.r.l. - www.assyoma.it email: g.danti(a)assyoma.it - info(a)assyoma.it GPG public key ID: FF5F32A8

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