June 2019 - dovecot - dovecot.org

Frequent Out of Memory for service(config)
by Root Kev 11 Jul '19

11 Jul '19

Hello Group, We have dovecot deployed as solely a Pop3 service that is used by our applications to pass mail from one application to another internally. We have roughly 4 applications that connect to the Pop3 service every 2 seconds, to check for new messages and pop them for processing if they are present. Depending on the site, we have between 1024-2048MB of memory set for default_vsz_limit. In all systems we see the Out of memory alert several times a day. We previously did not see this at all when running on CentOS6, with less memory. We have tried increasing the memory to the vsz_limit up to 2gb without success. We are running on CentOS 7 servers, running dovecot 2.3.6 (7eab80676) (from the dovecot repo). Can anyone advise any other settings that could be modified in order to correct these out of memory issues? # dovecot -n # 2.3.6 (7eab80676): /etc/dovecot/dovecot.conf # OS: Linux 3.10.0-957.5.1.el7.x86_64 x86_64 CentOS Linux release 7.6.1810 (Core) # Hostname: ****** #<modified for security> auth_cache_size = 10 M auth_verbose = yes default_vsz_limit = 1 G instance_name = Pop3 Mail Service listen = 10.*.*.* #<modified for security> log_path = /var/log/dovecot.log login_greeting = Pop3 Mail Service login_trusted_networks = 10.*.*.* 10.*.*.* 10.*.*.* 10.*.*.* 10.*.*.* #<modified for security> mail_location = maildir:~/Maildir namespace inbox { inbox = yes location = mailbox Drafts { special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Sent { special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { special_use = \Trash } prefix = } passdb { args = cache_key=#hidden_use-P_to_show# driver = pam } protocols = pop3 ssl_cert = </etc/pki/dovecot/certs/dovecot.pem ssl_key = # hidden, use -P to show it userdb { driver = passwd } verbose_ssl = yes May 10 06:44:05 config: Fatal: pool_system_malloc(8192): Out of memory May 10 06:44:05 config: Fatal: master: service(config): child 27887 returned error 83 (Out of memory (service config { vsz_limit=1024 MB }, you may need to increase it) - set CORE_OUTOFMEM=1 environment to get core dump) May 10 14:56:31 config: Fatal: pool_system_malloc(8192): Out of memory May 10 14:56:31 config: Fatal: master: service(config): child 2495 returned error 83 (Out of memory (service config { vsz_limit=1024 MB }, you may need to increase it) - set CORE_OUTOFMEM=1 environment to get core dump) May 10 23:09:02 config: Fatal: pool_system_malloc(8192): Out of memory May 10 23:09:02 config: Fatal: master: service(config): child 10581 returned error 83 (Out of memory (service config { vsz_limit=1024 MB }, you may need to increase it) - set CORE_OUTOFMEM=1 environment to get core dump) May 11 10:18:43 config: Fatal: pool_system_malloc(8192): Out of memory May 11 10:18:43 config: Fatal: master: service(config): child 30511 returned error 83 (Out of memory (service config { vsz_limit=1024 MB }, you may need to increase it) - set CORE_OUTOFMEM=1 environment to get core dump) May 11 18:30:59 config: Fatal: pool_system_malloc(1608): Out of memory May 11 18:30:59 config: Fatal: master: service(config): child 12134 returned error 83 (Out of memory (service config { vsz_limit=1024 MB }, you may need to increase it) - set CORE_OUTOFMEM=1 environment to get core dump) May 12 02:57:28 config: Fatal: pool_system_malloc(8192): Out of memory May 12 02:57:28 config: Fatal: master: service(config): child 24940 returned error 83 (Out of memory (service config { vsz_limit=1024 MB }, you may need to increase it) - set CORE_OUTOFMEM=1 environment to get core dump) May 12 11:07:34 config: Fatal: pool_system_malloc(8192): Out of memory May 12 11:07:35 config: Fatal: master: service(config): child 8203 returned error 83 (Out of memory (service config { vsz_limit=1024 MB }, you may need to increase it) - set CORE_OUTOFMEM=1 environment to get core dump) May 12 19:17:52 config: Fatal: pool_system_malloc(8192): Out of memory May 12 19:17:52 config: Fatal: master: service(config): child 14623 returned error 83 (Out of memory (service config { vsz_limit=1024 MB }, you may need to increase it) - set CORE_OUTOFMEM=1 environment to get core dump) May 13 03:26:34 config: Fatal: pool_system_malloc(8192): Out of memory May 13 03:26:35 config: Fatal: master: service(config): child 21479 returned error 83 (Out of memory (service config { vsz_limit=1024 MB }, you may need to increase it) - set CORE_OUTOFMEM=1 environment to get core dump) May 13 11:35:42 config: Fatal: pool_system_malloc(8192): Out of memory May 13 11:35:43 config: Fatal: master: service(config): child 26900 returned error 83 (Out of memory (service config { vsz_limit=1024 MB }, you may need to increase it) - set CORE_OUTOFMEM=1 environment to get core dump) May 13 19:34:26 config: Fatal: pool_system_malloc(8192): Out of memory May 13 19:34:26 config: Fatal: master: service(config): child 32187 returned error 83 (Out of memory (service config { vsz_limit=1024 MB }, you may need to increase it) - set CORE_OUTOFMEM=1 environment to get core dump). Thanks, Kevin

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Dovecot behind Load Balancer
by Paolo Daniele 10 Jul '19

10 Jul '19

Hi, i've a question for you. I've two dovecot imap/pop server behind a zen load balancer. Load balancing is made by lx4nat so the public ip address of my load balancer contact directly the dovecot servers. Since few months i've a message from thunderbird that i've reached the imap limit login for ip. I've triend to increase the max user ip parameter but sometimes i've the same problem. It's a strange things that actually i'm able to mitigate by reduce the number of cached connections in Thunderbird but it's not normal. What do you think about that? Maybe there's some tuning that you can suggest. Thank you, Paolo

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Applying Dovecot for a large / deep folder-hierarchy archive.
by Arnold Opio Oree 10 Jul '19

10 Jul '19

Hello to you all, I'd like to ask about my intended application of Dovecot to create a folder-hierarchy for storing our enterprise emails, which are treated as live data rather than archives for compliance or occasional / reactive retrieval. The data is presently not that large (a few gigabytes), but it is expected to grow rapidly. Up to this stage the data has been containedin a Microsoft Exchange mailbox (2013), and then in an offline PST. The move to the offline PST was by necessity, as the large number offolders, and depth of hierarchy to my best understanding caused the exchange server / outlook / evolution mail clients to begin tomalfunction. To cope with this the archive was broken up and the bulk stored in the offline PST and the most active components stored inonline Exchange mailboxes. I have some understanding of the fs mbox format, and also the mitigations to be made for certain characters / strings. My main concern is whether Dovecot is likely to be able to cope well with a large number of folders / depth of hierarcy. I will really appreciate any help / advice you can give. Best regards, Arnold Opio OreeChief Executive OfficerParallax Digital Technologies arnoldoree(a)parallaxdt.com http://www.parallaxdt.com tel : +44 (0) 333 577 8587fax : +44 (0) 20 8711 2477 Parallax Digital Technologies78A Hatfeild MeadLondonSM4 5PF Parallax Digital Technologies is a trading name of Parallax GlobalLimited. U.K. Co. No. 08836288 The contents of this e-mail are confidential. If you are not theintended recipient you are to delete this e-mail immediately, disregardits contents and disclose them to no other persons.

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Dovecot 2.3.0 TLS
by Hauke Fath 07 Jul '19

07 Jul '19

All, our dovecot installation provides a bundle of intermedia CA certificates using the ssl_ca option. 2.3.0 does not supply the bundle, resulting in various clients either complaining about an unverifiable server cert, or quietly not connecting. The log has Jan 5 17:01:46 Bounce dovecot: imap-login: Disconnected (no auth attempts in 0 secs): user=<>, rip=XXX, lip=YYY, TLS handshaking: SSL_accept() failed: error:14094416:SSL routines:SSL3_READ_BYTES:sslv3 alert certificate unknown: SSL alert number 46, session=<uKK/kAlia+GCUyU5> We fixed the issue by downgrading to 2.2.33.2. Cheerio, hauke -- The ASCII Ribbon Campaign Hauke Fath () No HTML/RTF in email Institut für Nachrichtentechnik /\ No Word docs in email TU Darmstadt Respect for open standards Ruf +49-6151-16-21344

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Repository / builds for Debian "buster"?
by Kostya Vasilyev 06 Jul '19

06 Jul '19

Speaking of repositories... Debian "buster" (future version 10) has for some time been "stage 1 frozen" (if I have the terminology right) and quite usable. Perhaps it's starting to make sense to make a repo / start producing builds? -- Kostya Vasilyev kman(a)fastmail.com

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Dovecot and Solr on the same server or on different
by Götz Reinicke 05 Jul '19

05 Jul '19

Hi. what would you suggest? What are the pros and cons for having dovecot and Solr on the same or different hots? I have about 800 accounts, some millions of mails and about 2 TB of zipped mails. From the recent experiences regarding maintenance I’d prefer different hosts for each. Thanks for suggestions and feedback . Götz

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Dovecot LMTP mixing up users on multi-recipient mail
by Bernhard Schmidt 03 Jul '19

03 Jul '19

Hi, I've upgraded a mailstore from Debian Jessie (aka oldstable) with Dovecot 2.2.13 to Debian Buster (next stable) with Dovecot 2.3.4.1 today. It worked pretty well, except that we're seeing error messages very similar to this old thread https://dovecot.org/pipermail/dovecot/2015-July/101396.html It appears to be happening when a mail with multiple recipients on this message store is getting delivered through lmtp. Jun 27 11:47:36 lxmhs74 dovecot: lmtp(user1)<47683><sGwaD7eQFF1DugAAgkzuhA:18>: Error: open(/var/cache/dovecot/index/n/user2n/.INBOX/dovecot.index.cache) failed: Permission denied (euid=3814520(<unknown>) egid=12(man) missing +x perm: /var/cache/dovecot/index/n/user2, dir owned by 3391995:12 mode=0700) user1 uid is 3814520, user2n uid is 3391995. Dovecot appears to be trying to deliver the message to user1 while using the index directory of user2n. Further configuration: - message store is on NFS - cache directory is on local disk - users are coming from LDAP, one UID per user user_attrs = cn=user,homeDirectory=home,uidNumber=uid,gidNumber=gid - index directory is calculated from the username maildir:~/Maildir:INDEX=/var/cache/dovecot/index/%-1.1n/%n Despite the error messages (which appear dozens of times per delivery attempt) delivery seems to work. Workaround was to set lmtp_destination_recipient_limit = 1 on the postfix in front of the message store. Despite the report linked above being quite old, I can't recall having issues with 2.2.13. === doveconf -n === # OS: Linux 4.19.0-5-amd64 x86_64 Debian 10.0 # Hostname: lxmhs74.srv.lrz.de default_vsz_limit = 512 M deliver_log_format = from=<%e>, size=%p, message-id=<%m>, status=%$ imap_id_log = * imap_id_send = * lda_mailbox_autocreate = yes lda_mailbox_autosubscribe = yes login_greeting = Dovecot ready. login_log_format_elements = user=<%u> method=%m rip=%r lip=%l mpid=%e %c session=<%{session}> cipher=<%k> mail_gid = mstore mail_location = maildir:~/Maildir:INDEX=/var/cache/dovecot/index/%-1.1n/%n mail_plugins = quota listescape mail_uid = mstore 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 mmap_disable = yes namespace inbox { inbox = yes location = mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox Junk { auto = subscribe special_use = \Junk } mailbox Sent { auto = subscribe special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { auto = subscribe special_use = \Trash } prefix = INBOX. separator = . type = private } passdb { args = /etc/dovecot/dovecot-ldap.conf driver = ldap } plugin { quota = maildir quota_rule = *:storage=1024M quota_rule2 = INBOX.Trash:ignore quota_status_nouser = DUNNO quota_status_overquota = 452 4.2.2 Mailbox is full quota_status_success = DUNNO quota_warning = storage=95%% quota-warning 95 %u quota_warning2 = storage=90%% quota-warning 90 %u sieve = ~/currently-active-script.sieve sieve_dir = ~/sieve } pop3_uidl_format = %v-%u protocols = imap lmtp sieve pop3 quota_full_tempfail = yes service anvil { client_limit = 3000 unix_listener anvil { group = sudo mode = 0660 } } service auth { client_limit = 3000 unix_listener auth-userdb { group = mstore mode = 0660 user = mstore } } service imap-login { client_limit = 1024 inet_listener imap { port = 143 } inet_listener imaps { port = 993 ssl = yes } process_limit = 2500 process_min_avail = 4 service_count = 0 } service imap { process_limit = 8192 } service lmtp { inet_listener lmtp { port = 24 } } service managesieve-login { inet_listener sieve { port = 4190 } inet_listener sieve_deprecated { port = 2000 } service_count = 1 } service managesieve { process_limit = 1024 } service pop3-login { inet_listener pop3 { port = 110 } inet_listener pop3s { port = 995 ssl = yes } } service quota-status { client_limit = 20 executable = quota-status -p postfix inet_listener { port = 12340 } } service quota-warning { executable = script /etc/dovecot/quotawarnmsg.sh unix_listener quota-warning { group = mstore mode = 0660 user = mstore } user = mstore } service stats { process_limit = 8192 } ssl_cert = </etc/dovecot/dovecot.pem ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it userdb { driver = prefetch } userdb { args = /etc/dovecot/dovecot-ldap-userdb.conf driver = ldap } verbose_proctitle = yes protocol imap { mail_plugins = quota listescape imap_quota imap_zlib } protocol lda { mail_plugins = quota listescape sieve } protocol lmtp { mail_plugins = quota listescape sieve } remote 127.0.0.1 { disable_plaintext_auth = no } remote ::1 { disable_plaintext_auth = no } === Thanks, Bernhard

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Dovecot/MSQL issue
by Nathan 02 Jul '19

02 Jul '19

Hello, I'm trying to work through an issue that cropped up on a server I've been working on and haven't found a very good workaround. Dovecot is operating in a jailed environment. The configuration in dovecot-sql.conf.ext has been set appropriately with the host=127.0.0.1 (which works from a jailed environment) and when dovecot attempts to auth it appears to perform a reverse dns lookup and overwrites the host with the result localhost before using the msql credentials 'user'@'localhost' which then fails after timing out. I'm currently running version 2.2.33.2 of dovecot. The workaround seems to be to have two credentials for the same user. 'user@'localhost' and 'user'@'127.0.0.1'; postfix operates in a jail as well and works around the jail issue in the same way but doesn't overwrite the specified host with a reverse dns lookup. Anyone have any suggestions on how to handle this issue better? or maybe there's a way to force different behavior which I haven't yet found in the documentation? Any help is much appreciated. Best Regards.

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virtual users, change password on first login?
by David Mehler 29 Jun '19

29 Jun '19

Hello, I've got an email server setup all with virtual users. There only interaction with it will be via a webmail interface in this case roundcube. What I'm wanting to do is set up automatic password change on first login. Would this be considered a dovecot or a roundcube issue? Any solution appreciated. Thanks. Dave.

2 1

Error: quota-status: Client sent invalid recipient address: Invalid character in path
by Lefteris Tsintjelis 29 Jun '19

29 Jun '19

Any idea what this is? Jun 26 23:16:34 quota-status(user(a)example.com)<4975><CLsXEzfSE11vEwAArt9ycg>: Error: quota-status: Client sent invalid recipient address: Invalid character in path I have this enabled in my config service quota-status { client_limit = 1 executable = quota-status -p postfix unix_listener /var/spool/postfix/private/dovquota { mode = 0666 user = postfix } } Lefteris

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