October 2021 - dovecot

2.3.14: stale imap-login processes due to bogus user setup tying up process limit
by Volker Stolz 16 Dec '22

16 Dec '22

I just dealt with an interesting Dovecot issue on our small server, and thought I might share it. I also feel that although in the end it was a configuration error, Dovecot should somehow avoid leaving this processes around and hence filling up the process limit quickly. - set up Dovecot IMAP on Debian buster (either with the older 2.3.x Debian package, or 2.3.14 from the dovecot-repo) - config: ... namespace inbox { inbox = yes location = ... default settings ... ... passdb { args = scheme=HMAC-MD5 username_format=%u /etc/dovecot/users driver = passwd-file } protocols = " imap" ... userdb { args = blocking=no driver = passwd } ... - secret sauce: have a user in the passdb that doesn't have a physical account on the system yet (we were migrating to a new machine). The log-file shows successful authentication for that user (after we flipped DNS to point to this new machine), but over time (2-3 times/day) we were left with an increasing number of `imap-login` processes in state `pre-login`, eventually requiring a dovecot restart. Dialling up process_limits didn't seem to help, we'd just get more of these stale processes. After creating the user on the system, the behaviour reverted to normal, no more stale processes. I do not know what error message that user received on their end, but since we announced we were migrating, they probably just ignored it and thought it as part of the transition. Best, Volker (a happy & long Dovecot user)

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Catch all for Metadata storage in SQL database
by Steffen Kaiser 27 Oct '22

27 Oct '22

Hi, the https://doc.dovecot.org/configuration_manual/imap_metadata/ sample uses mail_attribute_dict = file:%h/Maildir/dovecot-attributes which stores all keys=value pairs in the file. http://dovecot.2317879.n4.nabble.com/Dovecot-v2-3-9-3-HTTP-API-Endpoint-for… uses a SQL dict, however very specific ones. How can I use a SQL dict to store _all_ keys, as with a file based storage? I cannot find a documentation for "pattern" specification, that works as "catch all", in order to store anything not catched by patterns into the database. https://wiki.dovecot.org/Dictionary does not give any hint (in my eyes). -- Steffen Kaiser

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Unclear how to get both user and domain quotas to work
by Hans van Zijst 10 Sep '22

10 Sep '22

Hi, First of all: my apologies for this long message. I'm trying to post all the information anybody could need to help me on my way. What I'm trying to make is an installation where both users and domains can have quotas. Ideally I would configure a quota for a domain and set a quota of 0 for all users within that domain, so that mail will be accepted up to the point where the domain quota is reached. Setting up user quota was fairly easy, there's lots of documentation around and examples to take inspiration from. Not so much for domain quota however, or I'm really bad at searching the Net. I'm running Debian Bullseye here: MariaDB 10.5.12 Dovecot 2.3.13 Postfixadmin 3.3.10 I want to use dictionaries in MySQL, because eventually this will be a platform with several Dovecot and Postfix servers. At this time I'm only running one Dovecot installation and a few Postfix servers (two for communication with the outside world and one to do the virus and spam scanning). My current setup for user quota is how Postfixadmin wants it: MariaDB [postfixadmin]> desc quota2; +----------+--------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +----------+--------------+------+-----+---------+-------+ | username | varchar(100) | NO | PRI | NULL | | | bytes | bigint(20) | NO | | 0 | | | messages | int(11) | NO | | 0 | | +----------+--------------+------+-----+---------+-------+ 3 rows in set (0.001 sec) In /etc/dovecot/conf.d/90-quota.conf I have this: plugin { quota = dict:User quota::proxy::sqlquota quota_rule = *:bytes=1024M quota_rule2 = Trash:bytes=+100M quota_vsizes = yes quota_status_success = DUNNO quota_status_nouser = DUNNO quota_status_overquota = "552 5.2.2 Mailbox is full" } dict { sqlquota = mysql:/etc/dovecot/dovecot-dict-sql.conf.ext } The SQL-configuration /etc/dovecot/dovecot-dict-sql.conf.ext is this: connect = host=... dbname=... user=... password=... map { pattern = priv/quota/storage table = quota2 username_field = username value_field = bytes } map { pattern = priv/quota/messages table = quota2 username_field = username value_field = messages } map { pattern = shared/expire/$user/$mailbox table = expires value_field = expire_stamp fields { username = $user mailbox = $mailbox } } I use LMTP to accept mail from Postfix; the quota-plugin is activated for LMTP, so every incoming mail should be counted. This works like a charm: if I don't configure a quota for a user, he gets the default 1GB, if I override it in Postfixadmin, then that's what he gets. I'm running quota-status on a TCP-port, so the gateway SMTP-servers can connect to Dovecot for a quotacheck to decide whether to accept or reject an incoming message. Again, this works flawlessly. I can't find any serious documentation about this mapping thing. In particular, what's with that "pattern"? All I can find in the documentation is: "The dict key must match exactly priv/quota/storage. The dict keys are hardcoded in the Dovecot code, so depending on what functionality you’re configuring you need to know the available dict keys used it." -- https://doc.dovecot.org/configuration_manual/dict/#dict-sql If anyone can point me at better documentation than the actual source code: please! I browsed through the quota-plugin source code, but I'm not a programmer and couldn't find what I thought I was looking for. That said, I'm not sure where I got the third "map" from, with the shared/expire pattern. I seem to have forgotten to document that bit of my journey. Now, domain quotas... I've tried all kinds of stuff, but at the moment I'm stuck with something that seems to almost work. I added a second quota root: plugin { quota2 = dict:Domain quota:%d:proxy::sqldomainquota quota2_rule = *:bytes=1024M quota2_status_success = DUNNO quota2_status_nouser = DUNNO quota2_status_overquota = "552 5.2.2 Domain quota exceeded" quota2_vsizes = yes } dict { sqldomainquota = mysql:/etc/dovecot/dovecot-dict-sql.conf.ext } This dict refers to the same mapping as the one for user quotas, and I think that's the way it should be. Please correct me if I'm wrong. This creates a new user in the quota2 table, by the name of just the domain. Unfortunately, it simply fills it with the numbers from the first user it can find in that domain, not all users in that domain combined. What I think I should do, is change something in the dict so that it sums up all users in that domain, something like this: SELECT SUM(bytes) FROM quota2 WHERE username LIKE '%@domain'; Problem is that I can't find anything useful online with regards to this, I'm not even sure if I'm thinking in the right direction here. Any hints, suggestions or corrections? Or pointers to articles or documentation I might have missed? Kind regards, Hans

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What is the state of SMTPUTF8 support?
by Sylvhem 02 Jun '22

02 Jun '22

Hi! It’s been some time since I last saw a mention of SMTPUTF8 here. Last time I heard about it, it was worked on. Does anybody have news about that? -- Sylvhem

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Shared mailboxes, users with dots and a bug in subscriptions
by Tobias Stein 17 May '22

17 May '22

Hi, i'm running Dovecot 2.3.14.alpha0 with shared namespaces and stumbled across some errors messages logged, when the list of subscribed mailboxes is queried by a client. For every distinct account of in the list of subscriptions two corresponding lines are logged: Jan 28 11:42:34 mx1 dovecot: auth: missing passwd file: /etc/dovecot/private/example/users Jan 28 11:42:34 mx1 dovecot: auth: missing passwd file: /etc/dovecot/private/example/users Jan 28 11:42:34 mx1 dovecot: auth: missing passwd file: /etc/dovecot/private/example/users Jan 28 11:42:36 mx1 dovecot: imap(example_user(a)example.com)<3638><xl6li/O5VsVfWxyn>: Error: mkdir(/var/run/dovecot/user-not-found/noc@example) failed: Permission denied (euid=109(vmail) egid=118(vmail) missing +w perm: /var/run/dovecot, dir owned by 0:0 mode=0755) Jan 28 11:42:36 mx1 dovecot: imap(example_user(a)example.com)<3638><xl6li/O5VsVfWxyn>: Error: mkdir(/var/run/dovecot/user-not-found/info@example) failed: Permission denied (euid=109(vmail) egid=118(vmail) missing +w perm: /var/run/dovecot, dir owned by 0:0 mode=0755) Jan 28 11:42:36 mx1 dovecot: imap(example_user(a)example.com)<3638><xl6li/O5VsVfWxyn>: Error: mkdir(/var/run/dovecot/user-not-found/root@example) failed: Permission denied (euid=109(vmail) egid=118(vmail) missing +w perm: /var/run/dovecot, dir owned by 0:0 mode=0755) Similar messages are logged, when invalid entries are listed in '/var/lib/dovecot/db/shared-mailboxes', which i already pruned and haven't received them anymore since. I think these errors are caused by an unintended behaviour when writing "~/Maildir/subscriptions", which looks (shortened) like this. V 2 INBOX/INBOX shared/noc@example com/INBOX shared/info@example com/INBOX shared/root@example com/test shared/root@example com/test test_sub The subscription-file.c explodes the name on every hierarchy separator ('.','\0') and inserts a TAB character. Unfortunately it also explodes on the DNS label delimiter „.‟. This should probably be fixed by passing a structure containing the required information to the formatter to distinguish mailboxes from domain-names. Subscription in combination with multiple domains and shared mailboxes seems broken to me. Actually i can't even explain to me, why it is working in face of the errors. :-) Unfortunately in Maildir++ the separator dot is hard-coded. There is a very old thread on this mailing list, that suggests using „auth_username_translation‟ to replace dots with a different character, but this idea is getting worse the longer i think about it. I absolutely dislike the idea to set LAYOUT=fs, namespace/separator = § to change the separators to split on, because this would mean to restructure the physical layout of all mailboxes (hierarchically) and mess around with lots of files. I attached a dovecot-sysreport to reproduce the behaviour. /etc/dovecot/private/example.com/users looks like this: ### user:password:uid:gid:(gecos):home:(shell):extra_fields noc:{SSHA512}_hash_:::::: info:{SSHA512}_hash_:::::: root:{SSHA512}_hash_:::::: Please correct me if i'm wrong or point me to a workaround, but i think the layout code needs some love. :-) Best regards Tobias

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FTS solr or xapian and Public Folders
by David Williams 13 May '22

13 May '22

Hi all I hope someone can help with this. I'm looking at setting up FTS on a Dovecot server which has some quite big pubic folders (100,000+ emails each) and would appreciate some info about how fts both Xapian and Solr works with public folders. As background of the folders can receive emails and I use a dummy user and an alias file to deliver them for example testfolder: dummy+Public/MYTESTFOLDER(a)example.com delivers email addressed to testfolder(a)example.com to MYTESTFOLDER in the namespace Public. Has anyone successfully setup FTS with public folders using either Xapian or Solr and what happens when one user changes a folder, does that change show up for other users? E.G.: When an email is delivered by dummy and indexed will that email be indexed for other users as well? Similarly what happens that when an email is moved between, deleted from or copied to public folders by one user will that change then show up for the other users or not? I guess the basic question is: Are public folders indexed once and then the indexes are made available to each user with access or are they indexed for each user? Any info or experience that anyone has will be appreciated. Many thanks David

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test-file-cache.c needs #ifdef HAVE_RLIMIT_AS
by Rupert Gallagher 07 Feb '22

07 Feb '22

test-file-cache.c:259:24: error: use of undeclared identifier 'RLIMIT_AS' test_assert(getrlimit(RLIMIT_AS, &rl_cur) == 0); ^ test-file-cache.c:267:24: error: use of undeclared identifier 'RLIMIT_AS' test_assert(setrlimit(RLIMIT_AS, &rl_new) == 0); ^ test-file-cache.c:270:24: error: use of undeclared identifier 'RLIMIT_AS' test_assert(setrlimit(RLIMIT_AS, &rl_cur) == 0); ^ test-file-cache.c:276:24: error: use of undeclared identifier 'RLIMIT_AS' test_assert(setrlimit(RLIMIT_AS, &rl_new) == 0); ^ test-file-cache.c:279:24: error: use of undeclared identifier 'RLIMIT_AS' test_assert(setrlimit(RLIMIT_AS, &rl_cur) == 0); ^

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Dsync replication - delayed replication (Sync lock)
by Daniel Botting 31 Jan '22

31 Jan '22

Hi, *Our setup:* Two Debian 10 machines that are setup to replicate mail between them, we have round robin DNS setup so a user can connect to either server. *What should happen:* Mail is delivered to either server and replicated across straight away to their mailbox on the other server so it does not matter which one they are connected to they will receive it fairly soon after delivery. *What actually happens:* In some instances the user will experience a delayed receipt of messages if they are not connected to the server that the message is initially delivered to, sometimes the delay is 5/10 minutes, we had a recent support ticket submitted where it was over an hour. Error message seen in mail.err: Sep 1 10:16:15 <host name> dovecot: dsync-local(<username>)<WELSGEERTl8FEAAAZJ7A9A>: Error: Couldn't lock /path/to/mailbox/.dovecot-sync.lock: fcntl(/path/to/mailbox/.dovecot-sync.lock, write-lock, F_SETLKW) locking failed: Timed out after 30 seconds (WRITE lock held by pid 3697) Process 3697 is dovecot/doveadm-server. *Doveconf -n output:* # 2.3.10.1 (a3d0e1171): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.10 (67bf5bd7) # OS: Linux 4.19.0-10-amd64 x86_64 Debian 10.5 # Hostname: <server hostname> auth_verbose = yes default_vsz_limit = 0 doveadm_password = # hidden, use -P to show it first_valid_gid = 8 first_valid_uid = 8 last_valid_gid = 8 last_valid_uid = 8 lda_mailbox_autocreate = yes lda_mailbox_autosubscribe = yes mail_gid = 8 mail_location = maildir:~/Maildir mail_plugins = " notify replication" mail_uid = 8 managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex im ap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext editheader imapfla gs 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 = /etc/dovecot/dovecot-ldap.conf.ext driver = ldap } plugin { mail_replica = tcps:<server being replicated to>:<port being used> sieve = ~/.dovecot.sieve sieve_dir = ~/sieve sieve_extensions = +editheader +imapflags } postmaster_address = postmaster@<domain address> protocols = " imap sieve pop3" replication_max_conns = 12 service aggregator { fifo_listener replication-notify-fifo { user = mail } unix_listener replication-notify { user = mail } } service auth { unix_listener /var/run/dovecot-exim-bridge { mode = 0660 user = Debian-exim } } service doveadm { inet_listener { port = <port being used for replication> ssl = yes } } service imap-login { inet_listener imap { port = 143 } } inet_listener imaps { port = 993 ssl = yes } process_limit = 512 process_min_avail = 4 service_count = 1 } service imap { process_limit = 1024 } service managesieve-login { inet_listener sieve { port = <sieve port> } process_min_avail = 1 service_count = 8 vsz_limit = 256 M } service managesieve { process_limit = 1024 } service replicator { process_min_avail = 1 unix_listener replicator-doveadm { mode = 0666 } } ssl = required ssl_cert = </path/to/ssl/cert/fullchain.pem ssl_cipher_list = ALL:!LOW:!SSLv2:!EXP:!aNULL ssl_client_ca_dir = /etc/ssl/certs ssl_key = # hidden, use -P to show it ssl_min_protocol = TLSv1.2 userdb { args = /etc/dovecot/dovecot-ldap.conf.ext driver = ldap override_fields = home=/var/mail/%u uid=mail gid=mail } protocol lda { mail_plugins = " notify replication sieve" } protocol imap { mail_max_userip_connections = 32 mail_plugins = " notify replication" } protocol sieve { mail_max_userip_connections = 10 managesieve_logout_format = bytes=%i/%o managesieve_max_line_length = 65536 } Kind regards Daniel

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public folders, ACLs
by Stefan G. Weichinger 06 Dec '21

06 Dec '21

greetings ... I got the following request from a customer where we run dovecot-2.3.15 on a debian server: They have a public folder with all their project-related subfolders inside: namespace { location = maildir:/home/vmail/oeffentlich prefix = Oeffentlich/ separator = / subscriptions = yes type = public } So far we don't have the mail_plugin ACL enabled. They want to be able to create projectfolders that aren't move/delete/rename-able by the users, only by some admins. But the users should be allowed to move mails between different projectfolders etc As far as I understand we can do that with Dovecot ACLs (although I am still figuring out how to properly design them ...). My questions: * if I enable the mail_plugin for ACLs, does that in any way change the behavior of existing mailboxes? afai understand: no. Only if ACL-lists exist in the various mailboxes, these get applied, right? I don't want to break things, and I want to avoid additional complexity for the non-public user mailboxes etc Maybe I can enable the plugin only for that public namespace? * maybe someone has a link to a similar setup? thanks in advance, Stefan

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sieve - segmentation fault
by kjonca＠o2.pl 01 Dec '21

01 Dec '21

I tried to experiment with "index" extension and I found that, in case "0" sieve-filter segfaults. example code was: --8<---------------cut here---------------start------------->8--- if header :index 0 :last :regex "received" "some regex here" { fileinto "dedicated mailbox" ; } --8<---------------cut here---------------end--------------->8--- KJ -- http://stopstopnop.pl/stop_stopnop.pl_o_nas.html I dote on his very absence. -- William Shakespeare, "The Merchant of Venice"

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