- dovecot - dovecot.org

[Dovecot] [Patch] Fix delay on imao-append
by Bruno Prémont 13 Jun '08

13 Jun '08

Dovecot version: 1.1-rc8, 1.1-rc9 System: Linux-2.6.2x User-Agent: claws-mail-3.3 and 3.4 When appending messages (e.g. copy from mailclient local folder or second server to dovecot imap folder) dovecot answers with: <tag> OK [APPENDUID <n> <m>] Append completed\r\n This answer often reaches the client as two or more TCP packets, the client (when not using TCP_NODELAY on its socket) ACKs with some delay. When copying lots of (small) messages this delay has a very negative impact on copy time even though there are lots of network and system resources available. Sample sniffer output on client host: ... 1 0.0000 claws dovecot IMAP Request: 14639 APPEND "Test" (\Seen) {853} 2 0.0033 dovecot claws IMAP Response: +OK 3 0.0034 claws dovecot IMAP Request: <message> 4 0.0096 dovecot claws IMAP Response: 14639 5 0.0467 claws dovecot TCP 33453 > imap [ACK] 6 0.0481 dovecot claws IMAP Response: OK [APPENDUID 1204729411 2] Append Completed. 7 0.0481 claws dovecot TCP 33453 > imap [ACK] ... The delay of about 35ms between packet 4 and its ACK in packet 5 causes copies from client to server to be extremely slow. (Client and server on same 100Mb LAN, same result if client and server are on same host) The attached patch makes dovecot send the whole answer in a single packet, thus not triggering the delay issue. As far as I found out the delay is generated by Naggle algorithm, this algorithm being used by Linux TCP stack for small packets with the aim of improving payload/overhead share. Bruno Prémont RESTENA Foundation

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[Dovecot] How many imap processes per user
by Martijn de Munnik 13 Jun '08

13 Jun '08

Hi, I'm using dovecot for the first time on a production server (before dovecot I used bincimapd). I have a question about the number of imap (not imap-login) processes created for a user. I've seen 100+ processes for just 1 user. So far it only occurs for 1 user, other users have just 1 imap process. I now the user is using thunderbird and 2 mailclients are logged in at the same time (one workstation and one laptop). Is there an issue with dovecot/thunderbird? info@dem 28596 15780 0 10:48:41 ? 0:02 imap info@dem 28933 15780 0 10:50:57 ? 0:01 imap info@dem 25627 15780 0 10:28:55 ? 0:00 imap info@dem 28938 28933 0 - ? 0:00 <defunct> info@dem 29472 15780 0 10:54:23 ? 0:00 imap info@dem 25628 25627 0 10:28:55 ? 0:00 rawlog /opt/csw/ libexec/dovecot/imap info@dem 29329 29327 0 - ? 0:00 <defunct> info@dem 29805 29801 0 - ? 0:00 <defunct> info@dem 24303 24300 0 10:20:46 ? 0:00 rawlog /opt/csw/ libexec/dovecot/imap info@dem 29941 15780 0 10:58:09 ? 0:00 imap info@dem 28480 28477 0 - ? 0:00 <defunct> info@dem 28329 15780 0 10:46:28 ? 0:03 imap info@dem 29177 29176 0 - ? 0:00 <defunct> info@dem 28749 28748 0 - ? 0:00 <defunct> info@dem 29801 15780 0 10:56:56 ? 0:00 imap info@dem 29180 29179 0 10:52:05 ? 0:00 rawlog /opt/csw/ libexec/dovecot/imap info@dem 29635 15780 0 10:55:35 ? 0:00 imap info@dem 29642 29635 0 - ? 0:00 <defunct> info@dem 28477 15780 1 10:47:37 ? 0:02 imap info@dem 28200 28199 0 - ? 0:00 <defunct> info@dem 29942 29941 0 10:58:09 ? 0:00 rawlog /opt/csw/ libexec/dovecot/imap info@dem 28597 28596 0 - ? 0:00 <defunct> info@dem 28330 28329 0 - ? 0:00 <defunct> info@dem 25610 25609 0 10:28:49 ? 0:00 rawlog /opt/csw/ libexec/dovecot/imap info@dem 28748 15780 0 10:49:48 ? 0:02 imap info@dem 25609 15780 0 10:28:49 ? 0:00 imap info@dem 29176 15780 0 10:52:05 ? 0:01 imap info@dem 29327 15780 0 10:53:12 ? 0:01 imap info@dem 29179 15780 1 10:52:05 ? 0:05 imap info@dem 28199 15780 0 10:45:22 ? 0:03 imap info@dem 29474 29472 0 - ? 0:00 <defunct> info@dem 24300 15780 0 10:20:46 ? 0:00 imap All those processes are really slowing down the server. Martijn

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[Dovecot] strange looking code and userdb errors
by Tony den Haan 13 Jun '08

13 Jun '08

hi, i'm trying to use passdb ldap and userdb prefetch, using the userdb_ prefixes in pass_attrs, and i get: passdb didn't return userdb entries looking at the code at auth/userdb-prefetch.c i see: if (auth_request->userdb_reply == NULL) { if (auth_request->auth->userdbs->next == NULL) { /* no other userdbs */ auth_request_log_error(auth_request, "prefetch", "passdb didn't return userdb entries"); } else { /* more userdbs, they may know the user */ auth_request_log_info(auth_request, "prefetch", "passdb didn't return userdb entries"); } callback(USERDB_RESULT_USER_UNKNOWN, auth_request); return; } is this really correct? if so it migth be a good idea to at least print different errors Tony

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[Dovecot] auth issues on centos5 with ldap backend
by Jurvis LaSalle 13 Jun '08

13 Jun '08

Hi, We've had some issues with auth. /var/log/secure is full of 1000s of these lines: Jun 4 19:12:08 khan dovecot-auth: pam_unix(dovecot:auth): authentication failure; logname= uid=0 euid=0 tty=dovecot ruser= rhost=127.0.0.1 user=user123 Users can usually login OK with their ldap credentials, but occasionally logins slow to a crawl if not outright fail, esp people checking mail through Squirrelmail. Things get better after a dovecot restart. Googling around, I thought if we switched the order or disabled the second passdb we had configured for our dovecotadmin account, these failures would go away but that did not happen. Any thoughts or additional info I can provide? Pardon the unusual install prefix. We're trying to keep the source install separated from the ancient dovecot rpm shipped in rhel5. Thanks, Jurvis [root@khan ~]# /etc/dovecot/sbin/dovecot -n # 1.0.13: /etc/dovecot-1.0.13/etc/dovecot.conf log_path: /var/log/dovecot.log info_log_path: /var/log/dovecot-info.log ssl_cert_file: /etc/pki/dovecot/certs/star.idi.harvard.edu.crt ssl_key_file: /etc/pki/dovecot/private/star.idi.harvard.edu.key login_dir: /etc/dovecot-1.0.13/var/run/dovecot/login login_executable: /etc/dovecot/libexec/dovecot/imap-login mail_location: maildir:/RAID5/mailboxes/%u maildir_stat_dirs: yes maildir_copy_with_hardlinks: yes imap_client_workarounds: outlook-idle delay-newmail auth default: executable: /etc/dovecot/libexec/dovecot/dovecot-auth master_user_separator: * debug: yes debug_passwords: yes passdb: driver: pam args: blocking=yes userdb: driver: passwd args: blocking=yes

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[Dovecot] Current opened sessions
by tutankamen 12 Jun '08

12 Jun '08

Is there in Dovecot a command or another way to show current opened sessions, I mean who is connected using IMAP ti the server? It could be useful to know if I can restart my server without dusturb any client. Thank you Tutan

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[Dovecot] Antispam plugin custom behavior?
by Kyle Wheeler 12 Jun '08

12 Jun '08

Hello, I currently have a setup on my system with what I call "magic folders" to enable spam filter training. Here's how it works: 1. If you have a false-negative, put the spam into the Spam.Report folder 2. If you have a false-positive (which has all kinds of ugly spamassassin protective markup in it), put the message into the Spam.NotSpam folder Currently what happens is that a cron job comes along every five minutes and processes the messages in those folders. In the case of the NotSpam folder, it strips the message of the spamassassin markup, retrains the bayesian net, and redelivers the message (e.g. via deliver). In the case of the Report folder, the message is used to train the bayesian net (among other things) and then deleted. I'd love to be able to trigger these actions when the mail is moved, rather than have a cron job inspecting the mailboxes. I looked into the antispam plugin (http://johannes.sipsolutions.net/Projects/dovecot-antispam) which seems nice but doesn't appear sufficiently generic for my needs. What would really work is if I could get it set up such that putting a message into either of those directories is turned into piping the message to a script of my choosing (a different one for each folder). Does anyone know a good way of getting my own custom behavior in here, or is my cronjob setup probably the best way? ~Kyle -- The optimist thinks this is the best of all possible worlds. The pessimist fears it is true. -- J. Robert Oppenheimer

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[Dovecot] quota-rewrite patch & userdb quota overriding
by Alan Premselaar 12 Jun '08

12 Jun '08

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I've spent the past couple of hours trying to figure this out by checking the wiki and googling, but haven't come up with anything that works yet. I just installed dovecot 1.0.14 with the quota-rewrite (1.09) patch and i'm trying to get the quota overridden via a passwd-file type userdb. I had 1.0.13 without the new quota style patched in working but having trouble figuring this out. any help would be appreciated. prior to the quota-rewrite patch (which i installed with the hopes of using quota_warn feature) i was able to put the following line into my passwd-file userdb and it was working: alan:*:1000:1000::/home/alan::userdb_quota=maildir:storeage=2048000:ignore=Sent (which is what I wanted) but now with the new quota definition style, I'm not sure what I need to define the extra fields as. here is dovecot -n: # 1.0.14: /usr/local/etc/dovecot.conf log_path: /var/log/dovecot.log protocols: imap imaps managesieve ssl_cert_file: /etc/pki/tls/certs/dovecot.pem ssl_key_file: /etc/pki/tls/private/dovecot.pem disable_plaintext_auth: no login_dir: /usr/local/var/run/dovecot/login login_executable(default): /usr/local/libexec/dovecot/imap-login login_executable(imap): /usr/local/libexec/dovecot/imap-login login_executable(managesieve): /usr/local/libexec/dovecot/managesieve-login login_greeting_capability(default): yes login_greeting_capability(imap): yes login_greeting_capability(managesieve): no verbose_proctitle: yes mail_location: maildir:~/Maildir mail_debug: yes maildir_copy_with_hardlinks: yes mail_executable(default): /usr/local/libexec/dovecot/imap mail_executable(imap): /usr/local/libexec/dovecot/imap mail_executable(managesieve): /usr/local/libexec/dovecot/managesieve mail_plugins(default): quota imap_quota mail_plugins(imap): quota imap_quota mail_plugins(managesieve): mail_plugin_dir(default): /usr/local/lib/dovecot/imap mail_plugin_dir(imap): /usr/local/lib/dovecot/imap mail_plugin_dir(managesieve): /usr/local/lib/dovecot/managesieve sieve_storage(default): sieve_storage(imap): sieve_storage(managesieve): ~/sieve sieve(default): sieve(imap): sieve(managesieve): ~/.dovecot.sieve auth default: ~ passdb: ~ driver: pam ~ userdb: ~ driver: passwd-file ~ args: /usr/local/etc/dovecot.passwd ~ userdb: ~ driver: passwd ~ socket: ~ type: listen ~ master: ~ path: /var/run/dovecot/auth-master ~ mode: 384 ~ user: dovecot ~ group: dovecot plugin: ~ quota_rule: *:storage=1G ~ quota_rule2: Trash:storage=100M thanks, alan -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.8 (Darwin) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAkhPd+cACgkQE2gsBSKjZHQNMACghSk7awVX1Aj5HVeo0KjRxyZc lT0AoLJA00SiYiefi2wNrAOt7L6N5eg4 =mA8L -----END PGP SIGNATURE-----

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[Dovecot] Wrong message information
by Anders 12 Jun '08

12 Jun '08

We have a few users that every so often get empty data in their message overview. From and subject are empty, and the date is 1-Jan-1970. When opening the message in full view, all things are fine. Also, the data in the actual maildir file is fine. It looks a lot like the issue described here: http://dovecot.org/list/dovecot/2008-March/029282.html The server is Linux, ext3, no NFS, and Dovecot 1.1.rc4. The few clients that have had this problem so far have been Outlook Express. What can be done to debug this? Thanks, Anders.

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[Dovecot] Mutually exclusive Exim setup instructions
by Karl Schmidt 12 Jun '08

12 Jun '08

The correct way has to be one or the other: http://wiki.dovecot.org/LDA/Exim are mutually exclusive with http://wiki.dovecot.org/HowTo/DebianStable It appears that exim can either call dovecot's LDA or make the delivery itself. There may be good reasons to do it one way or the other. ---------------------------------------------------------------- Karl Schmidt EMail Karl(a)xtronics.com Transtronics, Inc. WEB http://xtronics.com 3209 West 9th Street Ph (785) 841-3089 Lawrence, KS 66049 FAX (785) 841-0434 If you are not part of the solution, you are part of the precipitate. ----------------------------------------------------------------

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[Dovecot] outlook windows problem
by rashantha de silva 11 Jun '08

11 Jun '08

hello, client can not connect using outlook. has any of you noticed this problem. can not connect with imap or as pop. i am using a self signed certificate.

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