- dovecot - dovecot.org

Hitting wall at 2048 IMAP connections
by Ron Cleven 04 Feb '15

04 Feb '15

We are gradually rolling out Dovecot (IMAP only, no POP3) to our customer base. We are replicating between a pair of CentOS 7 boxes. All has been working wonderfully. However, to be sure our rollout continues to go smoothly, we put together a simple benchmark client program to fire up X persistent IMAP connections (using hundreds of mailboxes) that login, list the folders, select the INBOX, periodically FETCH an email from the INBOX, and otherwise sit in an IDLE loop. As long as we keep the number of concurrent IMAP connections under 2k, everything works fine. 2,000 processes generate a minimal load on the server. However, 2048 is a "hard limit" for number of IMAP processes on a box the way things are configured right now. The number (2048) is a bit too magical to be anything but a misconfiguration of either some kernel limit or a dovecot configuration limit. I have been unable to figure out where else to look. I have pasted in my dovecot config below along with the kernel setting for max_user_instances. Hoping someone can tell me what stupid mistake I have made or what else to check. Just an aside, we front-end this with a separate set of proxy servers that provide an SSL front-end, hence, no SSL in the dovecot config. /proc/sys/fs/inotify/max_user_instances = 4096 # 2.2.10: /etc/dovecot/dovecot.conf # OS: Linux 3.10.0-123.13.1.el7.x86_64 x86_64 CentOS Linux release 7.0.1406 (Cor e) auth_master_user_separator = * auth_mechanisms = plain login default_internal_user = sysadm default_login_user = sysadm default_vsz_limit = 512 M disable_plaintext_auth = no doveadm_password = ************** doveadm_port = 12345 imap_max_line_length = 128 k listen = * mail_gid = 2001 mail_location = maildir:~/Maildir mail_plugins = notify replication mail_uid = 2001 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 mbox_write_locks = fcntl 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 = scheme=PLAIN /z/imap/usr/master-users driver = passwd-file master = yes pass = yes } passdb { args = scheme=PLAIN username_format=%u /z/imap/usr/users driver = passwd-file } plugin { mail_replica = tcp:imap0s sieve = ~/.dovecot.sieve sieve_dir = ~/sieve sieve_max_actions = 32 sieve_max_redirects = 4 sieve_max_script_size = 1M } protocols = imap pop3 sieve service aggregator { fifo_listener replication-notify-fifo { mode = 0666 user = sysadm } unix_listener replication-notify { mode = 0666 user = sysadm } } service auth { unix_listener auth-userdb { mode = 0777 } } service doveadm { inet_listener { port = 12345 } user = sysadm } service imap { process_limit = 4096 } service managesieve-login { inet_listener sieve { port = 4190 } } service managesieve { process_limit = 4096 } service replicator { process_min_avail = 1 } ssl = no userdb { args = username_format=%u /z/imap/usr/users driver = passwd-file } protocol lda { mail_plugins = sieve notify replication } protocol imap { mail_max_userip_connections = 40 } protocol sieve { managesieve_max_line_length = 65536 }

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Corruption of index files
by Oliver Welter 04 Feb '15

04 Feb '15

Hi All, after upgrading my mail server (dovecot 1.1.7 -> 2.2.13) I get tons of messages about corrupted index files in the syslog ("Error: Corrupted transaction log" and "Warning: fscking index file .. dovecot.index". I tried flock and even dotlock, but the problems persist. The system is a VPS with an overlay filesystem which did work flawlessly with the old dovecot install and is not reporting any errors in the host machine. From time to time I get warnings about an exceeded inotify limit for the dovecot user - might this be a problem? Anybody has an idea what might be the cause those problems and how to track them down. Oliver -- Protect your environment - close windows and adopt a penguin!

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Upstart script for Poolmon
by Listas＠Adminlinux 03 Feb '15

03 Feb '15

Hi My servers are Ubuntu 14.04 and I'm needing to make a Upstart script for Poolmon. Does someone already made this and could to share with us ? Thanks! -- Thiago henrique

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Master user without pass=yes error
by Thomas HUMMEL 03 Feb '15

03 Feb '15

Hello Timo, I just tried the master user feature with a very simple setup (Dovecot v2.2.15) : !include auth-master.conf.ext -> passwd-file passdb !include auth-ldap.conf.ext -> ldap passdb (userdb prefetched) without auth_bind=yes without pass=yes I get this userdb lookup error : dovecot: auth: passwd-file(masteruser,157.99.64.42,master,<4Pgesh0OygCdY0Aq>): Master user logging in as normaluser dovecot: auth: Error: prefetch(normaluser,157.99.64.42,<4Pgesh0OygCdY0Aq>): userdb lookup not possible with only userdb prefetch dovecot: imap: Error: Internal auth failure (client-pid=10449 client-id=1) dovecot: imap-login: Internal login failure (pid=10449 id=1) (internal failure, 1 successful auths): user=<normaluser>, method=PLAIN, rip=157.99.64.42, lip=157.99.64.81, mpid=10570, TLS, session=<4Pgesh0OygCdY0Aq> with pass=yes, it works. Feb 2 17:51:24 langres dovecot: auth: passwd-file(masteruser,157.99.64.42,master,<YmjAwx0O0gCdY0Aq>): Master user logging in as normaluser Feb 2 17:51:24 langres dovecot: imap-login: Login: user=<normaluser>, method=PLAIN, rip=157.99.64.42, lip=157.99.64.81, mpid=11647, TLS, session=<YmjAwx0O0gCdY0Aq> I dont quite understand why because the documentation states that 'pass=yes' "means that Dovecot verifies that the login user really exists before allowing the master user to log in. Without the setting if a nonexistent login username is given,[...]" Here, 'normaluser' exists in the ldap passdb so, even with pass=no, I'm not supposed to be in the 'nonesxistent login username' case. Can you help ? thanks. -- Thomas Hummel | Institut Pasteur <hummel(a)pasteur.fr> | Groupe Exploitation et Infrastructure

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quote strings passed to sql
by Juan Bernhard 03 Feb '15

03 Feb '15

Hello list. I'm thinking to migrate the hole user db from system users to mysql. I already did it in a test environment, but something is annoying my OCD... I don't quote the variables username and password sent to the mysql server. I know, the mysql user that dovecot uses only has select rights, but it stills bother me, because its possible to do an useless sql code injection. Is there a way to quote that? Something like exim's quote_mysql? Saludos, Juan.

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Re: Uniqueness of dovecot mailbox-guids
by Christian Binder Stadt Freilassing 02 Feb '15

02 Feb '15

Can no one give some adivse on this issue? Thanks Christian

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LDAP: "unused" & "uid missing"
by Leander Schäfer 02 Feb '15

02 Feb '15

Does someone know what this means? It looks to me like it got the UID, yet it complains ... ? Also, why does it complain about attributes being unused, yet I use prefetch, so they will be used?! Log: [...] dovecot: auth: Debug: ldap(test(a)mydomain.tld,192.168.10.233,<Rl2CF+UNhgDAqArp>): result: mailStorageDirectory=/var/vmail mailUidNumber=2110 mailGidNumber=2110 mailQuotaStorage=10240 mailQuotaMessages=20; mailQuotaMessages,mailStorageDirectory,mailUidNumber,mailQuotaStorage,mailGidNumber unused dovecot: auth: Debug: ldap(test(a)mydomain.tld,192.168.10.233,<Rl2CF+UNhgDAqArp>): result: mailStorageDirectory=/var/vmail mailUidNumber=2110 mailGidNumber=2110 mailQuotaStorage=10240 mailQuotaMessages=20; uid missing [...] As mentioned, I use prefetch, so this is how my dovecot/dovecot-ldap.conf.ext is looking: [...] #user_attrs = mailStorageDirectory=home=%$/%u, mailStorageDirectory=mail=maildir:%$/%u/maildir, mailUidNumber=uid, mailGidNumber=gid, mailQuotaStorage=quota_rule=*:storage=%$, mailQuotaMessages=quota_rule2=*:messages=%$ pass_attrs = uid=user, userPassword=password, mailStorageDirectory=userdb_home=%$/%u, mailStorageDirectory=userdb_mail=maildir:%$/%u/maildir, mailUidNumber=userdb_uid, mailGidNumber=userdb_gid, mailQuotaStorage=userdb_quota_rule=*:storage=%$, mailQuotaMessages=userdb_quota_rule2=*:messages=%$ [...] Thanks

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Sieve permissions issue following update
by David Gessel 02 Feb '15

02 Feb '15

I recently updated dovecot and my sieve filters stopped working. Checking the logs I see: Dec 9 00:09:59 mailhost dovecot: lda(gessel(a)domain.com): Error: sieve: binary save: failed to create temporary file: open(/usr/local/etc/dovecot/sieve/10-move-spam.svbin.mailhost.domain.com.114.) failed: Permission denied (euid=5000(vmail) egid=5000(vmail) missing +w perm: /usr/local/etc/dovecot/sieve, we're not in group 6(mail), dir owned by 143:6 mode=0775) Dec 9 00:09:59 mailhost dovecot: lda(gessel(a)domain.com): Error: sieve: The LDA Sieve plugin does not have permission to save global Sieve script binaries; global Sieve scripts like `/usr/local/etc/dovecot/sieve/10-move-spam.sieve' need to be pre-compiled using the sievec tool However this fairly clear advice on the failure seems to be contradicted by: # id vmail uid=5000(vmail) gid=5000(vmail) groups=5000(vmail),6(mail) ? dovecot-pigeonhole-0.4.6 = up-to-date with index dovecot2-2.2.15_1 = up-to-date with index uname -a FreeBSD host.domain.com 9.3-RELEASE FreeBSD 9.3-RELEASE #0 r268932: Mon Jul 21 15:51:38 PDT 2014 gessel@host1.domain.com:/usr/obj/usr/src/sys/BARCELONA-13-08 amd64

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managesieve & checkpassword authdb interface
by Peter Hodur 02 Feb '15

02 Feb '15

Hello, does anybody knows what managesieve addon sets in SERVICE env when autentificating to checkpassword? thanks Pete

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Domain quota
by Evgeny Basov 02 Feb '15

02 Feb '15

Hello. I'm tried to use domain quota: plugin { quota = dict:Domain quota:%d:redis:host=127.0.0.1:prefix=domain/ quota_rule = *:storage=0 quota2 = dict:User quota::redis:host=127.0.0.1:prefix=user/ quota2_rule = *:storage=0 quota3_rule = Trash:storage=+5%% } but got next problem with it. Init state: # doveadm quota get -u "testacc(a)m.tld" Quota name Type Value Limit % Domain quota STORAGE 27070 204800 13 Domain quota MESSAGE 21 - 0 User quota STORAGE 27068 - 0 User quota MESSAGE 18 - 0 # doveadm quota get -u "testacc2(a)m.tld" Quota name Type Value Limit % Domain quota STORAGE 27070 204800 13 Domain quota MESSAGE 21 - 0 User quota STORAGE 2 - 0 User quota MESSAGE 3 - 0 Make recalc: # doveadm quota recalc -u "testacc2(a)m.tld" and got: # doveadm quota get -u "testacc2(a)m.tld" Quota name Type Value Limit % Domain quota STORAGE 2 204800 0 Domain quota MESSAGE 3 - 0 User quota STORAGE 2 - 0 User quota MESSAGE 3 - 0 # doveadm quota get -u "testacc(a)m.tld" Quota name Type Value Limit % Domain quota STORAGE 2 204800 0 Domain quota MESSAGE 3 - 0 User quota STORAGE 27068 - 0 User quota MESSAGE 18 - 0 All values of all domain quota are equals. Execute recalc one more time: # doveadm quota recalc -u "testacc(a)m.tld" # doveadm quota get -u "testacc(a)m.tld" Quota name Type Value Limit % Domain quota STORAGE 27068 204800 13 Domain quota MESSAGE 18 - 0 User quota STORAGE 27068 - 0 User quota MESSAGE 18 - 0 # doveadm quota get -u "testacc2(a)m.tld" Quota name Type Value Limit % Domain quota STORAGE 27068 204800 13 Domain quota MESSAGE 18 - 0 User quota STORAGE 2 - 0 User quota MESSAGE 3 - 0 How can I get fast realtime changed domain quota? Used dovecot 2.2.13.

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