- dovecot - dovecot.org

[Dovecot] IO rate quotas?
by Kádár Tamás (KTamas) 09 Apr '11

09 Apr '11

Hi Okay so we've been having this issue since forever and I figured why the heck not ask it here since it's mostly related to dovecot. The thing is, we have a huge amount of public folders (at the moment, around 1100). Now, with dovecot indexing and caching we're mostly okay, also being careful with things like Thunderbird 3's default 'Download everything' option ("Keep messages for this account on this computer") and such. However once in a while, someone goes rogue, we install a new version of thunderbird, someone accidentally sets up an email account in thunderbird mistakingly leaving the download everything option on. This causes high IO on our server, and a single user can quickly more or less kill the whole server in mere minutes, load average quickly spiking to 30-40-50 and everything becomes sloooooow (obviously). Is there any way I can limit the amount of IO a certain user can use? Thanks and best regards, KT P.S. my dovecot -n is: # 2.0.9: /usr/local/etc/dovecot/dovecot.conf # OS: Linux 2.6.26-2-xen-amd64 x86_64 Debian 5.0.8 auth_mechanisms = plain login disable_plaintext_auth = no listen = * mail_location = maildir:~/Maildir mail_plugins = acl maildir_very_dirty_syncs = yes namespace { inbox = yes location = prefix = separator = . type = private } namespace { location = maildir:/home/_shared/projects:INDEX=~/Maildir/_shared prefix = shared. separator = . subscriptions = no type = public } namespace { location = maildir:/home/_shared/sys:INDEX=~/Maildir/sys prefix = sys. separator = . subscriptions = no type = public } passdb { driver = pam } plugin { acl = vfile mail_log_events = delete undelete expunge copy mailbox_delete mailbox_rename flag_change append mail_log_fields = uid box msgid from subject size vsize flags mail_log_group_events = no } protocols = imap pop3 service imap { executable = imap } ssl_cert = </etc/ssl/certs/dovecot.pem ssl_key = </etc/ssl/private/dovecot.pem userdb { driver = passwd } verbose_proctitle = yes protocol imap { mail_max_userip_connections = 40 mail_plugins = acl imap_acl }

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[Dovecot] coredump in dovecot 2.0.11
by k b 09 Apr '11

09 Apr '11

Hi. I use dovecot-2.0.11-1.fc14.i686 on linux,redhat fedora 14. Using alpine 2.02 and Kmail 1.13.5 i have one IMAP connection to the dovecot server and one IMAP connection to a MS exchange server. After i moved a few messages from the exchange server i cannot open the folders where i placed the moved mails. instead dovecot crashes, all other directories and emails work fine. here is what i see in /var/log/messages: Apr 9 08:23:10 server00 abrt[28509]: saved core dump of pid 28508 (/usr/libexec/dovecot/imap) to /var/spool/abrt/ccpp-1302330190-28508.new/coredump (626688 bytes) Apr 9 08:23:10 server00 abrtd: Directory 'ccpp-1302330190-28508' creation detected Apr 9 08:23:10 server00 abrtd: Crash is in database already (dup of /var/spool/abrt/ccpp-1302111878-7921) Apr 9 08:23:10 server00 abrtd: Deleting crash ccpp-1302330190-28508 (dup of ccpp-1302111878-7921), sending dbus signal I can post the coredump but i will have to clean it first as i can see it contains a few emails. would it help to post the coredump or shuould i skip that?

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[Dovecot] mysql lookup on another host performance q?
by Voytek Eymont 09 Apr '11

09 Apr '11

Hi, new to dovecot I'm setting a small postfix/dovecot server for virtual domain/users in mysql dovecot is on one host, mysql on another seems to be working, but I'm concerned over performance overhead of this setup; dumb Q, is there any 'proxy mysql' or cacheing option I can use ? any suggestions appreciated also, my mail users as set as 5000/5000 virtual_gid_maps = static:5000 virtual_uid_maps = static:5000 so, I should use uid/gid 5000/5000 in query below, yes ? thanks -- Voytek --------------------------------------------------------- # dovecot --version 1.2.9 Linux 2.6.32-21-generic-pae #32-Ubuntu SMP Fri Apr 16 09:39:35 UTC 2010 i686 GNU/Linux # grep -v '^ *$#.*$\?$' dovecot-sql.conf driver = mysql connect = host=host.tld dbname=ddd user=ccc 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' 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'

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[Dovecot] 143 STARTTLS/ 993 SSL/TLS query
by Voytek Eymont 09 Apr '11

09 Apr '11

I'm testing my new dovecot server with Thundirbird I can have it working on port 143 with STARTTLS, or on port 993 with SSL/TLS my uderstanding is that on 993 I get encrypted 'password and mail transfer' (yes ?) so what happens if I use 143 with STARTTLS, is that equivalent to port 993 if STARTTLS is used ? thanks for any insights.. -- Voytek

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Re: [Dovecot] Permission Denied - cannot create inbox
by Joseph Tam 09 Apr '11

09 Apr '11

Timo Sirainen <tss(a)iki.fi> writes: > This is anyway mbox-specific problem, so I added it now to mbox page: > > http://wiki2.dovecot.org/MailLocation/mbox ... >> imap(tss): Error: >> fchown(/home/tss/mail/.imap/INBOX/dovecot.index.log.newlock, >> group=8(mail)) failed: Operation not permitted (egid=1000(tss), group >> based on /var/mail/tss - see http://wiki2.dovecot.org/Errors/NoPerm) >> > Changed the wiki link: http://wiki2.dovecot.org/Errors/ChgrpNoPerm Thanks, Timo. This will be opaque to the user, but I don't think it will happen often so it's no bother to find the problem in the logs. Joseph Tam <jtam.home(a)gmail.com>

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[Dovecot] Imap segfault on login with version 2.0.8 & 2.0.11
by Nicholas VonHollen 09 Apr '11

09 Apr '11

Hi everyone, I'm trying to upgrade/test our configuration files from Dovecot 1.2 to 2.0.11. I used the Dovecot config convert command, created a RHEL 5 x86_64 rpm, and tested it. I can connect, but once I login, the IMAP service segfaults. I've also reproduced this on version 2.0.8. I installed the debug RPM (for the stripped symbols), took a look at the core dump in gdb, and just got the _start method in ld_preload and a broken pointer in the backtrace. I tried to strace everything but the segfault doesn't happen then :-). I'm not sure what to do to get better information. I attached my client session, dovecot -n output, gdb trace, maillog, and the core dump. I published the RPMs I made at: http://c3205012.r12.cf0.rackcdn.com/dovecot-2.0.11-1_125.x86_64.rpm http://c3205012.r12.cf0.rackcdn.com/dovecot-debuginfo-2.0.11-1_125.x86_64.r… My platform is RHEL 5 with kernel 2.6.18 on x86_64. Is there anything else I can provide for more info? Thanks, Nick Nick VonHollen Rackspace Software Developer Desk: 540-443-2003 (internal 505-2003) Personal Cell: 757-710-7038

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[Dovecot] restarting director
by Cor Bosman 08 Apr '11

08 Apr '11

Hi all, anyone having any problems with restarting the director? Every time I bring down 1 of the director servers, reboot it, or just restart it for whatever reason, im seeing all kinds of problems. Dovecot generally always gives me this error: Jan 20 22:49:55 imapdirector3 dovecot: director: Error: Director 194.109.26.173:444/right disconnected before handshake finished It seems the directors cant agree on forming a ring anymore, and this may be leading to problems with clients. I mostly have to resort to bringing down all directors, and restarting them all at once. Not really a workable solution. As an example, last night for a few hours we were getting complaints from customers about being disconnected, and the only obvious error in the log was the one above, after one of my colleagues had to restart a director because of some changes in the syslog daemon. After I restarted all directors withing a few seconds of each other, all complaints disappeared. Timo, i know ive asked similar questions before, but the answer just eludes me. If I have 3 director servers, and need to take one down and restart it, what is the proper method to reconnect the ring? In practice, I cant seem to work it out and I mostly end up with the above error until I just restart them all. Not fun with 20.000 clients connected. Cor

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[Dovecot] Thunderbird 3.1 unable to delete subfolder of Trash under mdbox
by William Blunn 08 Apr '11

08 Apr '11

Thunderbird 3.1.9 over Windows 7. Dovecot 2.0.11 (2:2.0.11-0~auto+41 from http://xi.rename-it.nl/debian/ source on 8 Apr 2011) over Ubuntu 10.04 LTS. Trying to set up a Dovecot system with mdbox. But I also wanted to keep some Maildir. So I ended up with both mdbox and Maildir side-by-side and noticed an issue. On this system, Dovecot's global mail location is configured with maildir:~/Maildir I have a two users configured in a password-file passdb/userdb: One using the Dovecot global mail location (maildir:~/Maildir) the other with an override mail location (userdb_mail) of mdbox:~/mdbox (The only other configurations different to the default were to turn off the default system password passdb and userdb, and enable my local password-file-format passdb and userdb.) I have configured two IMAP accounts in Thunderbird 3.1.9, one to access each of the two users above. The test procedure is: In Thunderbird, create a folder at the top level (i.e. alongside Inbox), say "foo". In Thunderbird, delete the folder just created. This results in Thunderbird "moving" the folder to "Trash", resulting in a folder "Trash/foo". Up to this point, both the Maildir and mdbox users behave OK. Then in Thunderbird, delete the trashed folder "Trash/foo". At this point, things start to happen differently. With the Maildir user, the folder "Trash/foo" deletes successfully. But with the mdbox user, Thunderbird pops up an error: The current command did not succeed. The mail server for account <accountname> responded: Invalid mailbox name: Trash/foo/. The folder does disappear from the Thunderbird folder pane, but if Thunderbird is "prodded" to refresh what folders it thinks are there, then the folder reappears. If we check the user's mdbox directory, we can see that indeed the mailbox has not been deleted. Whatever I then do, I am unable to delete this folder in the mdbox user through Thunderbird. The only way I have found to safely delete the folder is to use "doveadm mailbox delete", but this requires root privilege on the server, which is not really a practical solution. It maybe a Thunderbird problem, but the question then arises: Why does it work under Maildir but doesn't work under mdbox? Any ideas? Bill

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[Dovecot] fstat no such file or directory error
by Mark Dieterich 08 Apr '11

08 Apr '11

Periodically, we will have users IMAP sessions get hung. Their client sees a message like: The server responded: 'SERVERBUG] Internal error occurred. Refer to server log for more information On the server, we see the following in the logs: IMAP(<username>): Transaction log dovecot.index.log: duplicate transaction log sequence (37) IMAP(<username>): fscking index file dovecot.index IMAP(<username>): fstat() failed with index file dovecot.index: No such file or directory After the fstat message shows up, there doesn't appear to be anything on the user side that can be done to fix the problem. We've seen multiple instances where the file dovecot is complaining about not existing is visible, readable, and writable by the user in question, but dovecot is convinced it's not. The only way we've found to fix this issue is to kill off all user connections. When the user reconnects, then all appears to work fine. We have not found a way to recreate this problem. Some details: # 1.2.15: /etc/dovecot/dovecot.conf # OS: Linux 2.6.26-2-686 i686 Debian 5.0.8 Mail files are stored on NFS. All imap connections for a given user are are mapped to a particular server at any given time. We have a script in place that watches our logs for this order of events, so the problem self corrects relatively quickly. But it would certainly be nice not have this happen at all. Thanks, Mark -- ---------- I'd rather be burning carbohydrates than hydrocarbons

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[Dovecot] a strange doveadm behavior
by fakessh ＠ 08 Apr '11

08 Apr '11

hi timo very very good job you realize for the community here I have a very strange problem with doveadm I actually use a configuration file parameters in which the parameters are placed carefully My problem appears when I run this command doveadm expunge -A mailbox Trash savedbefore 30d i post command and result to the terminal [fakessh@r13151 ~]$ doveadm expunge -A mailbox Trash savedbefore 30d doveadm(fakessh): Error: userdb lookup: connect(/var/run/dovecot//auth-userdb) failed: Permission denied (euid=514(fakessh) egid=100(users) missing +r perm: /var/run/dovecot//auth-userdb, euid is not dir owner) doveadm: Error: Failed to iterate through some users [root@r13151 ~]$ chmod +r /var/run/dovecot/auth-userdb [fakessh@r13151 ~]$ doveadm expunge -A mailbox Trash savedbefore 30d doveadm(fakessh): Error: userdb lookup: connect(/var/run/dovecot//auth-userdb) failed: Permission denied (euid=514(fakessh) egid=100(users) missing +w perm: /var/run/dovecot//auth-userdb, euid is not dir owner) doveadm: Error: Failed to iterate through some users [root@r13151 ~]# chmod og+w /var/run/dovecot/auth-userdb [fakessh@r13151 ~]$ doveadm expunge -A mailbox Trash savedbefore 30d doveadm(dkimproxy): Fatal: seteuid(0) failed: Operation not permitted [fakessh@r13151 ~]$ any kind of discussion would be welcome -- gpg --keyserver pgp.mit.edu --recv-key 092164A7 http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x092164A7

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