- dovecot - dovecot.org

[Dovecot] Configuration advice needed.
by Olivier Girard 03 Jun '13

03 Jun '13

Hello, First, thanks for this great piece of software. I'm new to dovecot and i've just converted my old courier configuration on pop/imap server side, everithing is working just fine on this side and speed gain expected was found (not enough for our busy servers :). Setup is done with 3 dovecot virtual servers load balanced with a Hardware load balancer (this part is a big point of the question). Postfix and dovecot servers use an NFS share on a NetApp for mail, Postfix servers are writting directly to inbox maildirs. Load balanced is maintaining afinity betwen client and server so i've got no problem with this for the moment. Now, i want to setup postfix (3 HW load balanced) for local delivery with LMTP on deovecot servers, and here come my questions. Afinity can't be maintained between IMAP and LMTP for a user with my load balancer so mail can be delivered on dovecot01 and read on dovecot02, from what i've read this can be an issue with indexes. I think i need to setup a director to maintain LMTP and IMAP afinity between users and servers but on imap servers i'm identifying user with their UID, and LMTP need to see emails. Does dovecot see the same user or 2 users with the same homedir? So my question is: could you point me to the right direction with this setup, do you have any advice on this config. Actual configurations: (postlogin not in real use, just a touch on (imap/pop3)_last_login) POP/IMAP server: dovecot01# doveconf -n # 2.1.15: /usr/local/etc/dovecot/dovecot.conf # OS: FreeBSD 8.3-RELEASE-p3 amd64 auth_cache_negative_ttl = 0 auth_cache_size = 10 M auth_mechanisms = plain login auth_verbose = yes default_client_limit = 1500 default_process_limit = 500 default_vsz_limit = 1 G disable_plaintext_auth = no dotlock_use_excl = no lock_method = dotlock mail_fsync = always mail_gid = vmail mail_location = maildir:%h/Maildir:INDEX=/mail_index%h mail_nfs_index = yes mail_nfs_storage = yes mail_plugins = " stats" mail_uid = vmail mmap_disable = yes namespace { inbox = yes location = prefix = INBOX. separator = . } passdb { args = /usr/local/etc/dovecot/dovecot-ldap.conf.ext driver = ldap } plugin { stats_refresh = 30 secs stats_track_cmds = yes } protocols = imap pop3 service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } user = $default_internal_user } service imap-postlogin { executable = script-login /usr/local/bin/imap-postlogin.sh user = vmail } service imap { executable = imap imap-postlogin process_limit = 1024 } service pop3-postlogin { executable = script-login /usr/local/bin/pop3-postlogin.sh user = vmail } service pop3 { executable = pop3 pop3-postlogin process_limit = 1024 } service stats { fifo_listener stats-mail { mode = 0600 user = vmail } } ssl_cert = </etc/ssl/cert/mail.univ-angers.fr.pem ssl_key = </etc/ssl/cert/mail.univ-angers.fr.key userdb { args = /usr/local/etc/dovecot/dovecot-ldap.conf.ext driver = ldap } protocol imap { mail_plugins = " stats imap_stats" } Postfix Test Server: %doveconf -n # 2.1.15: /usr/local/etc/dovecot/dovecot.conf # OS: FreeBSD 8.3-RELEASE-p3 amd64 auth_debug = yes auth_mechanisms = plain login auth_verbose = yes default_client_limit = 1500 default_process_limit = 500 default_vsz_limit = 512 M disable_plaintext_auth = no dotlock_use_excl = no lock_method = dotlock mail_fsync = always mail_gid = vmail mail_location = maildir:%h/Maildir:INDEX=/mail_index%h mail_nfs_index = yes mail_nfs_storage = yes mail_uid = vmail mmap_disable = yes namespace { inbox = yes location = prefix = INBOX. separator = . } passdb { args = /usr/local/etc/dovecot/dovecot-ldap.conf.ext driver = ldap } protocols = lmtp service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } unix_listener auth-userdb { user = vmail } user = $default_internal_user } service imap-postlogin { executable = script-login /usr/local/bin/imap-postlogin.sh user = vmail } service imap { executable = imap imap-postlogin process_limit = 1024 } service lmtp { inet_listener lmtp { address = * :: port = 24 } process_min_avail = 20 user = vmail } service pop3-postlogin { executable = script-login /usr/local/bin/pop3-postlogin.sh user = vmail } service pop3 { executable = pop3 pop3-postlogin process_limit = 1024 } ssl_cert = </etc/ssl/cert/mail.univ-angers.fr.pem ssl_key = </etc/ssl/cert/mail.univ-angers.fr.key userdb { args = /usr/local/etc/dovecot/dovecot-ldap.conf.ext driver = ldap } File dovecot-ldap.conf.ext uris = ldap://ldap.uang dn = cn=acces-smtp, ou=access, dc=univ-angers, dc=fr dnpass = ********** base = ou=people, dc=univ-angers, dc=fr user_attrs = homeDirectory=home user_filter = (&(|(uid=%u) (mail=%u) (auaAliasEmail=%u))(|(auaStatut=etu)(auaStatut=etu-sortant)(auaStatut=perso)(auaStatut=perso-sortant))) pass_attrs = uid=user,userPassword=password pass_filter = (&(|(uid=%u) (mail=%u) (auaAliasEmail=%u)) (|(auaStatut=etu)(auaStatut=etu-sortant)(auaStatut=perso) (auaStatut=perso-sortant))) iterate_attrs = uid=user iterate_filter = (|(auaStatut=etu)(auaStatut=etu-sortant)(auaStatut=perso)(auaStatut=perso-sortant)) default_pass_scheme = MD5-CRYPT

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[Dovecot] An unconstructive grumble
by dd 03 Jun '13

03 Jun '13

5 hours of configuration attempts, error after confusing error, documentation with examples that only show extracts of working configurations. I really feel like throwing in the towel with dovecot. It should not be this hard and frankly almost impossible to understand and configure for such an incedibly simple configuration. /home/vmail/domain.name/username/cur /home/vmail/domain.name/username/new /home/vmail/domain.name/username/tmp 3 virtual users. All I want is a username and password to access my email. I have to have hit every error and problem there can be. No response at all from server, unable to find password file, unable to recognise user, invalid password. God it went on and on and on for five or more hours. For such a simple config. I know this is a totally unconstructive complaint and I should be taking the time to set out a careful explanation of my problem along with errors and logfiles but I just can't be bothered. I've tried so many many configurations and options and nothing works. How can it possibly be this hard to ghet some emails off the server with simple username/password configurations. Go ahead and flame me to a crisp. -- View this message in context: http://dovecot.2317879.n4.nabble.com/An-unconstructive-grumble-tp42598.html Sent from the Dovecot mailing list archive at Nabble.com.

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[Dovecot] Settings: Dovecot + NTLM + Single Sing On + Windows + Outlook or Thunderbird.
by Maria Jose Yañez Dacosta 03 Jun '13

03 Jun '13

I am following the steps listed in: http://wiki.dovecot.org/HowTo/ActiveDirectoryNtlm My goal is to have single sign-on for Microsoft Outlook applications. I working and I have some doubts since I never set up an imap server, hope I can help :). The version that I have installed is devecot 2.0.9. "dovecot -n" shows the following: # 2.0.9: /etc/dovecot/dovecot.conf # OS: Linux 2.6.32-71.el6.x86_64 x86_64 CentOS release 6.4 (Final) auth_use_winbind = yes mbox_write_locks = fcntl passdb { driver = pam } protocols = imap pop3 ssl = no userdb { args = uid=10000 gid=10000 home=/mail/%d/%n driver = static } I show what I have in /etc/samba/smb.conf [global] workgroup = EJEMPLO realm = EJEMPLO.COM.UY server string = %h (Samba %v) security = ADS password server = ad.domain.dom username map = /etc/samba/mapeousuarios map untrusted to domain = Yes syslog = 0 log file = /var/log/samba/log.%m max log size = 1000 name resolve order = wins host bcast local master = No domain master = No dns proxy = No wins server = here active directory ip panic action = /usr/share/samba/panic-action %d winbind separator = + winbind use default domain = Yes winbind rpc only = Yes idmap config * : range = 1200-3000 idmap config * : backend = tdb [usuarios3] path = /exports/archivos-usuarios read only = No map acl inherit = Yes store dos attributes = Yes "wbinfo -g" and "wbinfo -u" work well. kinit Administrator work well also. Some steps of the configuration in dovecot.conf does not recognize: 1) "protocols = imap imaps pop3 pop3s". 2) "mechanisms = plain ntlm login". 3) "allow_all_users=yes" y "mail=maildir:/home/vmail/%d/%1Ln/%Ln:INBOX=/home/vmail/%d/%1Ln/%Ln". I'm not sure I should put in place. I also have some doubts: 1) I have to create a keytab file containing the principal for imap and pop?, as it would indicate Dovecot?. 2) That should indicate values uid y el gid? 3) I have to set something in pam? if I make "telnet localhost imap" shows the following: OK [CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE IDLE AUTH=PLAIN] Dovecot ready NTLM not appears in the options. I hope I can shed some light on the subject :) Thanks and greetings. -- Maria José

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[Dovecot] =Davide Pasquale=
by Davide Pasquale 02 Jun '13

02 Jun '13

http://archiv.isusice.eu/ewcyozyg/fltdigdpmijtefzkeuuepzdutvxu.hnfzuk

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Re: [Dovecot] MS asks for feedback on standards support in Outlook/Exchange
by Robert Schetterer 01 Jun '13

01 Jun '13

Am 01.06.2013 13:40, schrieb Timo Sirainen: > On 1.6.2013, at 9.35, Robert Schetterer <rs(a)sys4.de> wrote: > >> Am 01.06.2013 00:28, schrieb Timo Sirainen: >>> Someone should at least mention that they should support the real SPECIAL-USE instead of just Gmail-specific XLIST.. >> >> i cant see any major Problems recent with i.e outlook 2013 and dovecot >> and SPECIAL-USE, perhaps look the screens at > > What about http://dovecot.org/list/dovecot/2013-May/090489.html ? > --- Outlook 2013 is only working when adding XLIST manually to imap_capability imap_capability = +XLIST --- i dont have this on my servers, and outlook 2013 works with special use as expected perhaps this helps http://social.technet.microsoft.com/Forums/de-DE/officeitpro/thread/eacaa11… --- You're welcome. Regarding your questions: Exchange 2010 and its supported (and unsupported and deviations from) IMAP standards are described on MS-STANXIMAP (MSDN). As far as I can tell, neither XLIST nor the enhanced (=extension of the standard) version of LIST is supported. Please keep in mind that this wouldn't matter very much, since most would connect to an Exchange 2010 server using either ActiveSync or MAPI/RPC. The following scenarios would definitely work: (A) your provider allows connections using ActiveSync (often referred to as "mobile" connection/access) and you're using Outlook 2013, (B) your provider allows connections using MAPI/RPC and you're using Outlook 2010. Outlook 2013 supports the extension specified in RFC 6154 and implements it using the XLIST command (as per MS-STANOIMAP), as documented in MS-STANOIMAP part 2.2.38; however, the LIST command in the same document doesn't mention the extension, so I'd assume it (Outlook 2013) doesn't necessarily support this feature using LIST as specified per RFC6154 (but only using explicitly XLIST.) Usually, any newer IMAP server supporting RFC6154 "LIST" ("XLIST") supports both the older XLIST as well as the newer LIST syntax. If it doesn't, a patch implementing this feature shouldn't be longer than a few (10 maybe?) lines of code and a few kind words to the developer team to get it into the next release of the server in question. --- http://msdn.microsoft.com/en-us/library/ee624430%28v=exchg.80%29.aspx ----------- V0061: The specification describes how to define an experimental command or any command that is not part of the specification. Microsoft Office Outlook 2007, Microsoft Outlook 2010 Outlook does not define any such commands. Microsoft Outlook 2013 Outlook 2013 implements the IMAP LIST extension specified in [RFC6154] as the XLIST command. --------------- so it may more a typical microsoft doku problem *g but however ,in fact no working trouble with dovecot SPECIAL-USE as far i remmeber to that list posting the problem whas there should get fixed was outlooks meaning of the Junk folder stuff, which is basicly done in another way by having its own antispam feature setup, so there are a few way to workaround that problem which i never tested and never will. My simple answer always is, Outlook is the client of exchange, with few stuff supporting normal internet mail ( imap etc ), dont use it with internet mail or live with its problems for notice Horde will implement Outlook 2013 complete active sync stack , so if that will happen, use active sync modus outlook 2013 with calender, abook, push mail , should no need for direct imap server con then, and it should "feel" like using exchnage ( but i think for one account only ), as horde has caldav and carddav , syncml too it can be used as middleware between many clients on many different os types i.e thunderbird lightning and k9 or native androids mail clients in exchange mode Best Regards MfG Robert Schetterer -- [*] sys4 AG http://sys4.de, +49 (89) 30 90 46 64 Franziskanerstraße 15, 81669 München Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263 Vorstand: Patrick Ben Koetter, Axel von der Ohe, Marc Schiffbauer Aufsichtsratsvorsitzender: Florian Kirstein Best Regards MfG Robert Schetterer -- [*] sys4 AG http://sys4.de, +49 (89) 30 90 46 64 Franziskanerstraße 15, 81669 München Sitz der Gesellschaft: München, Amtsgericht München: HRB 199263 Vorstand: Patrick Ben Koetter, Axel von der Ohe, Marc Schiffbauer Aufsichtsratsvorsitzender: Florian Kirstein

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[Dovecot] v2.2.2 (7b1152c83e3e) latest changes break LMTP
by Thomas Leuxner 01 Jun '13

01 Jun '13

Suppose this one breaks it: http://hg.dovecot.org/dovecot-2.2/rev/c4a85c9df948 ==> /var/log/mail.log <== Jun 1 14:01:30 spectre postfix/lmtp[456]: 3bN0qP5kwFzSy: to=<tlx(a)leuxner.net>, relay=spectre.leuxner.net[private/dovecot-lmtp], delay=1481, delays=1481/0/0.01/0.01, dsn=4.3.0, status=deferred (host spectre.leuxner.net[private/dovecot-lmtp] said: 451 4.3.0 <tlx(a)leuxner.net> Temporary internal error (in reply to end of DATA command)) ==> /var/log/dovecot/dovecot.log <== Jun 1 14:01:30 spectre dovecot: lmtp(523): Error: Can't open delivery mail as raw: Invalid mailbox name: Name is empty Regards Thomas

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[Dovecot] real and virtual users
by devocotml＠fuckaround.org 01 Jun '13

01 Jun '13

Hi all! I use debian with real users (pam) and virtual users: I receive mail from virtual users but not from real users. Real users can connect and do login but no email received :-( Any idea? thanks! dovecot -n # 1.2.15: /etc/dovecot/dovecot.conf # OS: Linux 2.6.32-5-686 i686 Debian 6.0.7 log_path: /var/log/dovecot.log log_timestamp: %Y-%m-%d %H:%M:%S protocols: pop3s ssl_cert_file: /etc/dovecot/ssl/dovecotpop.crt ssl_key_file: /etc/dovecot/ssl/dovecotpop.key login_dir: /var/run/dovecot/login login_executable: /usr/lib/dovecot/pop3-login mail_location: maildir:~Maildir mbox_write_locks: fcntl dotlock mail_executable: /usr/lib/dovecot/pop3 mail_plugin_dir: /usr/lib/dovecot/modules/pop3 lda: auth_socket_path: /var/run/dovecot/auth-master postmaster_address: max(a)nuvolabianca.org mail_plugins: sieve log_path: /var/log/dovecot-lda.log log_path: auth default: mechanisms: plain login verbose: yes passdb: driver: passwd-file args: scheme=SHA256 /etc/dovecot/v_users.conf passdb: driver: pam userdb: driver: static args: uid=5000 gid=5000 home=/home/vhosts/%d/%n allow_all_users=yes socket: type: listen client: path: /var/spool/postfix/private/auth mode: 432 user: postfix group: postfix master: path: /var/run/dovecot/auth-master mode: 384 user: vmail group: vmail

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[Dovecot] Fwd: MS asks for feedback on standards support in Outlook/Exchange
by Timo Sirainen 01 Jun '13

01 Jun '13

Someone should at least mention that they should support the real SPECIAL-USE instead of just Gmail-specific XLIST.. Begin forwarded message: > From: Andrew Laurence <atlauren(a)me.com> > Subject: [imapext] MS asks for feedback on standards support in Outlook/Exchange > Date: 1. kesäkuuta 2013 1.18.42 UTC+3.00 > To: HIED-EMAILADMIN(a)LISTSERV.ND.EDU, windows-hied(a)lists.stanford.edu, office365(a)ucdavis.edu, imapext(a)ietf.org > > Hello everyone, > > Forgive the massive list cross-posting, but I thought this noteworthy enough to spread around. > > Via their Openness@Microsoft blog, Microsoft invites input on their standards support in Outlook and Exchange. I'm sure they'd like to hear thoughtful, detailed, insightful responses from the customer world at large. > http://blogs.technet.com/b/openness/archive/2013/05/31/feedback-exchange-se… > > Cheers, > Andrew > -- > Andrew Laurence Office of Information Technology > atlauren(a)uci.edu University of California, Irvine > atlauren(a)me.com (Lists) > > _______________________________________________ > imapext mailing list > imapext(a)ietf.org > https://www.ietf.org/mailman/listinfo/imapext

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[Dovecot] dovecot-lmtp does not work
by He Shiming 01 Jun '13

01 Jun '13

Dear Community, I've got a weird problem regarding lmtp setup with dovecot 2.0.19 on ubuntu 12.04.2 LTS. My reference of the configuration is at https://library.linode.com/email/postfix/postfix2.9.6-dovecot2.0.19-mysql , and my configuration is identical to it with the exception of opening the 110 pop3 port, and enabling plain text auth. Everything from imap, smtp, pop3 (including auth) works except for lmtp. I saw thousands of the following messages in /var/log/mail.log: May 31 09:05:24 postfix/lmtp[3664]: 2FD80321F4: to=<myaddress(a)me.com>, relay=none, delay=0.41, delays=0.41/0/0/0, dsn=4.4.1, status=deferred (connect to me.com[private/dovecot-lmtp]: No such file or directory) And it happens when an incoming email is received. Here's the output of configuration: root@prosp:/etc/dovecot/conf.d# dovecot -n # 2.0.19: /etc/dovecot/dovecot.conf # OS: Linux 3.8.4-linode50 i686 Ubuntu 12.04.2 LTS ext3 auth_mechanisms = plain login disable_plaintext_auth = no mail_location = maildir:/var/mail/vhosts/%d/%n mail_privileged_group = mail 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 { args = /etc/dovecot/dovecot-sql.conf.ext driver = sql } plugin { sieve = ~/.dovecot.sieve sieve_dir = ~/sieve } protocols = imap pop3 sieve service auth-worker { user = vmail } service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } unix_listener /var/spool/postfix/private/dovecot-auth { group = postfix mode = 0660 user = postfix } unix_listener auth-userdb { mode = 0600 user = vmail } user = dovecot } service imap-login { inet_listener imap { port = 0 } } service lmtp { unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0600 user = postfix } } service pop3-login { inet_listener pop3 { port = 110 } } 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 { args = uid=vmail gid=vmail home=/var/mail/vhosts/%d/%n driver = static } 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 } This problem has been discussed here: http://serverfault.com/questions/512219/dovecot-lmtp-does-not-exist . I've then tried switching from unix socket to inet listener, and still got the same result. I cannot get lmtp service to start. I'm also seeing no errors in the log when dovecot is restarted (see the above link for the log). I'm wondering how do I go about troubleshooting this problem? What might be the possible cause? Is it possible for dovecot to output verbose logs regarding service startups? Thank you. -- Best regards, He Shiming *Kaoya.me <http://kaoya.me> | Goals.io<http://itunes.apple.com/us/app/goals.io-realize-your-dreams/id496228828?ls=…> | Toppin'Wiper <https://itunes.apple.com/app/toppinwiper/id553527232?mt=8> | MediaMan <http://www.imediaman.com>*

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[Dovecot] imapc "moving email to another folder" crashes
by Michael Miller 01 Jun '13

01 Jun '13

Hello List, I am having the same problem with dovecot 2.2.1 on RHEL and dovecot 2.2.2 on FreeBSD and the imapc proxy. moving eMail from one folder to another folder. the error is reproducible. Logfile RHEL/Dovecot 2.2.1: May 31 19:57:45 imap(mail(a)--------.com): Panic: file mail-storage.c: line 2100 (mailbox_copy): assertion failed: (!ctx->unfinished) May 31 19:57:45 imap(mail(a)--------.com): Error: Raw backtrace: /usr/lib64/dovecot/libdovecot.so.0(+0x5f68a) [0x7fd60b76a68a] -> /usr/lib64/dovecot/libdovecot.so.0(+0x5f6d6) [0x7fd60b76a6d6] -> /usr/lib64/dovecot/libdovecot.so.0(+0x1fffa) [0x7fd60b72affa] -> /usr/lib64/dovecot/libdovecot-storage.so.0(+0x792f2) [0x7fd60ba402f2] -> dovecot/imap() [0x40bebb] -> dovecot/imap(command_exec+0x3d) [0x41502d] -> dovecot/imap() [0x414190] -> dovecot/imap() [0x41427d] -> dovecot/imap(client_handle_input+0x11d) [0x4144fd] -> dovecot/imap(client_input+0x6f) [0x41486f] -> /usr/lib64/dovecot/libdovecot.so.0(io_loop_call_io+0x36) [0x7fd60b7799d6] -> /usr/lib64/dovecot/libdovecot.so.0(io_loop_handler_run+0xa7) [0x7fd60b77aa87] -> /usr/lib64/dovecot/libdovecot.so.0(io_loop_run+0x28) [0x7fd60b779978] -> /usr/lib64/dovecot/libdovecot.so.0(master_service_run+0x13) [0x7fd60b72fa63] -> dovecot/imap(main+0x2a9) [0x41dcf9] -> /lib64/libc.so.6(__libc_start_main+0xfd) [0x7fd60b396cdd] -> dovecot/imap() [0x40a579] May 31 19:57:45 imap(mail(a)--------.com): Fatal: master: service(imap): child 27742 killed with signal 6 (core dumped) Logfile FreeBSD / Dovecot 2.2.2: May 31 19:53:41 imap(mail(a)--------.com): Panic: file mail-storage.c: line 2105 (mailbox_copy): assertion failed: (!ctx->unfinished) May 31 19:53:41 imap(mail(a)--------.com): Fatal: master: service(imap): child 2077 killed with signal 6 (core not dumped) the configuration is more or less the same on both: # 2.2.1: /etc/dovecot/dovecot.conf # OS: Linux 2.6.32-358.6.2.el6.x86_64 x86_64 CentOS release 6.4 (Final) auth_mechanisms = plain login first_valid_uid = 97 imapc_host = imap.upstreamserver.com log_path = /var/log/dovecot.log mail_gid = dovecot mail_home = /clusterdata2/imapcache/%u mail_location = imapc:~/imapc mail_uid = dovecot passdb { args = host=imap.upstreamserver.com default_fields = userdb_imapc_user=%u userdb_imapc_password=%w driver = imap } protocols = imap service auth { unix_listener auth-client { mode = 0666 user = dovecot } } service imap { drop_priv_before_exec = yes } ssl_cert = </etc/ssl/imap-myserver-de.crt ssl_key = </etc/ssl/imap_myserver-de.key userdb { driver = prefetch } and finally the coredump from RHEL/Dovecot 2.2.1: # gdb /usr/libexec/dovecot/imap core GNU gdb (GDB) Red Hat Enterprise Linux (7.2-60.el6_4.1) Copyright (C) 2010 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html> This is free software: you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. Type "show copying" and "show warranty" for details. This GDB was configured as "x86_64-redhat-linux-gnu". For bug reporting instructions, please see: <http://www.gnu.org/software/gdb/bugs/>... Reading symbols from /usr/libexec/dovecot/imap...(no debugging symbols found)...done. [New Thread 27742] Reading symbols from /usr/lib64/dovecot/libdovecot-storage.so.0...(no debugging symbols found)...done. Loaded symbols for /usr/lib64/dovecot/libdovecot-storage.so.0 Reading symbols from /usr/lib64/dovecot/libdovecot.so.0...(no debugging symbols found)...done. Loaded symbols for /usr/lib64/dovecot/libdovecot.so.0 Reading symbols from /lib64/libc.so.6...(no debugging symbols found)...done. Loaded symbols for /lib64/libc.so.6 Reading symbols from /lib64/librt.so.1...(no debugging symbols found)...done. Loaded symbols for /lib64/librt.so.1 Reading symbols from /lib64/libdl.so.2...(no debugging symbols found)...done. Loaded symbols for /lib64/libdl.so.2 Reading symbols from /lib64/ld-linux-x86-64.so.2...(no debugging symbols found)...done. Loaded symbols for /lib64/ld-linux-x86-64.so.2 Reading symbols from /lib64/libpthread.so.0...(no debugging symbols found)...done. [Thread debugging using libthread_db enabled] Loaded symbols for /lib64/libpthread.so.0 Reading symbols from /lib64/libnss_files.so.2...(no debugging symbols found)...done. Loaded symbols for /lib64/libnss_files.so.2 Reading symbols from /lib64/libgcc_s.so.1...(no debugging symbols found)...done. Loaded symbols for /lib64/libgcc_s.so.1 Core was generated by `dovecot/imap'. Program terminated with signal 6, Aborted. #0 0x00007fd60b3aa8a5 in raise () from /lib64/libc.so.6 Missing separate debuginfos, use: debuginfo-install dovecot-2.2.1-0_134.el6.x86_64 (gdb) bt full #0 0x00007fd60b3aa8a5 in raise () from /lib64/libc.so.6 No symbol table info available. #1 0x00007fd60b3ac085 in abort () from /lib64/libc.so.6 No symbol table info available. #2 0x00007fd60b76a698 in ?? () from /usr/lib64/dovecot/libdovecot.so.0 No symbol table info available. #3 0x00007fd60b76a6d6 in ?? () from /usr/lib64/dovecot/libdovecot.so.0 No symbol table info available. #4 0x00007fd60b72affa in i_panic () from /usr/lib64/dovecot/libdovecot.so.0 No symbol table info available. #5 0x00007fd60ba402f2 in mailbox_copy () from /usr/lib64/dovecot/libdovecot-storage.so.0 No symbol table info available. #6 0x000000000040bebb in ?? () No symbol table info available. #7 0x000000000041502d in command_exec () No symbol table info available. #8 0x0000000000414190 in ?? () No symbol table info available. #9 0x000000000041427d in ?? () No symbol table info available. #10 0x00000000004144fd in client_handle_input () No symbol table info available. #11 0x000000000041486f in client_input () No symbol table info available. #12 0x00007fd60b7799d6 in io_loop_call_io () from /usr/lib64/dovecot/libdovecot.so.0 No symbol table info available. #13 0x00007fd60b77aa87 in io_loop_handler_run () from /usr/lib64/dovecot/libdovecot.so.0 No symbol table info available. #14 0x00007fd60b779978 in io_loop_run () from /usr/lib64/dovecot/libdovecot.so.0 No symbol table info available. #15 0x00007fd60b72fa63 in master_service_run () from /usr/lib64/dovecot/libdovecot.so.0 No symbol table info available. #16 0x000000000041dcf9 in main () No symbol table info available. (gdb) any ideas ?

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