September 2018 - dovecot

doveadm quota error output in some cases
by Kai Schaetzl 05 Oct '18

05 Oct '18

I am testing a special setup on one machine where I want to put some local users that get mail locally to /home user directories via postfix transport map local: for historical and practical reasons. Other users are setup as virtual users. The local users are *also* setup as virtual users for dovecot so that I can retrieve the mail via dovecot. I changed the SQL for dovecot user_query, so that it gets the local uid and gid (and doesn't use vmail) and also gets the home directory in /home for only those users. After a bit of experimenting this works fine and I can retrieve mail via dovecot. However, there are two problems with quota and one of them has "doveadm get quota" spew out a lot of garbage that I think should actually go to a log and not to the program output. When I run a doveadm quota get -A or -u user I get four errors of this kind (for user/domain storage and message limit) for each special user: doveadm(user): Error: Failed to get quota resource STORAGE: quota-dict: dict_lookup(priv/quota/storage) failed: net_connect_unix (/var/run/dovecot/dict) failed: Permission denied (euid=500(user) egid=200(vmail) missing +r perm: /var/run/dovecot/dict, dir owned by 0:0 mode=0755) (reply took 0.000 secs (0.000 in dict wait, 0.000 in other ioloops, 0.000 in locks)) Then the normal program output follows, with error lines for these special users, of course: user STORAGE error error error The reason is that /var/run/dovecot/dict is owned by vmail:vmail (not root:root as the 0:0 suggests). I don't see a way to change this without blocking the "real" virtual users that use vmail:vmail. Shouldn't this massive error output rather go to a log? (dovecot/error.log) Or: is there a way to avoid this? /var/run/dovecot/dict is a socket. I didn't want to fiddle with it. Can I change the permissions so that it can also be accessed by other system users? Probably only to make it world-readable? If so, what are the implications of doing that? Thanks, Kai

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Username aliases
by Eirik Rye 05 Oct '18

05 Oct '18

Hi, Our organization is currently using a passwd-file user database for our Dovecot installs. However, we now want to provide simple username aliases. We currently use usernames that are -not- equal to the email address, but due to the fact that many major email clients/providers do not even allow you to specifiy a username, we now want to provide aliases where the username is equal to the email address. A simple solution would be to duplicate the lines in the passwd-file, with the email address as the username, but this does not seem be ideal due to data duplication. Ideally, there would be a secondary 'alias' userdb, which on a match would then restart the search in the primary passwd-file userdb using the new username. Is this possible? What would be the best way to go about this?

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Re: [ceph-users] dovecot + cephfs - sdbox vs mdbox
by Webert de Souza Lima 04 Oct '18

04 Oct '18

Thanks Jack. That's good to know. It is definitely something to consider. In a distributed storage scenario we might build a dedicated pool for that and tune the pool as more capacity or performance is needed. Regards, Webert Lima DevOps Engineer at MAV Tecnologia *Belo Horizonte - Brasil* *IRC NICK - WebertRLZ* On Wed, May 16, 2018 at 4:45 PM Jack <ceph(a)jack.fr.eu.org> wrote: > On 05/16/2018 09:35 PM, Webert de Souza Lima wrote: > > We'll soon do benchmarks of sdbox vs mdbox over cephfs with bluestore > > backend. > > We'll have to do some some work on how to simulate user traffic, for > writes > > and readings. That seems troublesome. > I would appreciate seeing these results ! > > > Thanks for the plugins recommendations. I'll take the change and ask you > > how is the SIS status? We have used it in the past and we've had some > > problems with it. > > I am using it since Dec 2016 with mdbox, with no issue at all (I am > currently using Dovecot 2.2.27-3 from Debian Stretch) > The only config I use is mail_attachment_dir, the rest lies as default > (mail_attachment_min_size = 128k, mail_attachment_fs = sis posix, > ail_attachment_hash = %{sha1}) > The backend storage is a local filesystem, and there is only one Dovecot > instance > > > > > Regards, > > > > Webert Lima > > DevOps Engineer at MAV Tecnologia > > *Belo Horizonte - Brasil* > > *IRC NICK - WebertRLZ* > > > > > > On Wed, May 16, 2018 at 4:19 PM Jack <ceph(a)jack.fr.eu.org> wrote: > > > >> Hi, > >> > >> Many (most ?) filesystems does not store multiple files on the same > block > >> > >> Thus, with sdbox, every single mail (you know, that kind of mail with 10 > >> lines in it) will eat an inode, and a block (4k here) > >> mdbox is more compact on this way > >> > >> Another difference: sdbox removes the message, mdbox does not : a single > >> metadata update is performed, which may be packed with others if many > >> files are deleted at once > >> > >> That said, I do not have experience with dovecot + cephfs, nor have made > >> tests for sdbox vs mdbox > >> > >> However, and this is a bit out of topic, I recommend you look at the > >> following dovecot's features (if not already done), as they are awesome > >> and will help you a lot: > >> - Compression (classic, https://wiki.dovecot.org/Plugins/Zlib) > >> - Single-Instance-Storage (aka sis, aka "attachment deduplication" : > >> https://www.dovecot.org/list/dovecot/2013-December/094276.html) > >> > >> Regards, > >> On 05/16/2018 08:37 PM, Webert de Souza Lima wrote: > >>> I'm sending this message to both dovecot and ceph-users ML so please > >> don't > >>> mind if something seems too obvious for you. > >>> > >>> Hi, > >>> > >>> I have a question for both dovecot and ceph lists and below I'll > explain > >>> what's going on. > >>> > >>> Regarding dbox format (https://wiki2.dovecot.org/MailboxFormat/dbox) > >> when > >>> using sdbox, a new file is stored for each email message. > >>> When using mdbox, multiple messages are appended to a single file until > >> it > >>> reaches/passes the rotate limit. > >>> > >>> I would like to understand better how the mdbox format impacts on IO > >>> performance. > >>> I think it's generally expected that fewer larger file translate to > less > >> IO > >>> and more troughput when compared to more small files, but how does > >> dovecot > >>> handle that with mdbox? > >>> If dovecot does flush data to storage upon each and every new email is > >>> arrived and appended to the corresponding file, would that mean that it > >>> generate the same ammount of IO as it would do with one file per > message? > >>> Also, if using mdbox many messages will be appended to a said file > >> before a > >>> new file is created. That should mean that a file descriptor is kept > open > >>> for sometime by dovecot process. > >>> Using cephfs as backend, how would this impact cluster performance > >>> regarding MDS caps and inodes cached when files from thousands of users > >> are > >>> opened and appended all over? > >>> > >>> I would like to understand this better. > >>> > >>> Why? > >>> We are a small Business Email Hosting provider with bare metal, self > >> hosted > >>> systems, using dovecot for servicing mailboxes and cephfs for email > >> storage. > >>> > >>> We are currently working on dovecot and storage redesign to be in > >>> production ASAP. The main objective is to serve more users with better > >>> performance, high availability and scalability. > >>> * high availability and load balancing is extremely important to us * > >>> > >>> On our current model, we're using mdbox format with dovecot, having > >>> dovecot's INDEXes stored in a replicated pool of SSDs, and messages > >> stored > >>> in a replicated pool of HDDs (under a Cache Tier with a pool of SSDs). > >>> All using cephfs / filestore backend. > >>> > >>> Currently there are 3 clusters running dovecot 2.2.34 and ceph Jewel > >>> (10.2.9-4). > >>> - ~25K users from a few thousands of domains per cluster > >>> - ~25TB of email data per cluster > >>> - ~70GB of dovecot INDEX [meta]data per cluster > >>> - ~100MB of cephfs metadata per cluster > >>> > >>> Our goal is to build a single ceph cluster for storage that could > expand > >> in > >>> capacity, be highly available and perform well enough. I know, that's > >> what > >>> everyone wants. > >>> > >>> Cephfs is an important choise because: > >>> - there can be multiple mountpoints, thus multiple dovecot instances > on > >>> different hosts > >>> - the same storage backend is used for all dovecot instances > >>> - no need of sharding domains > >>> - dovecot is easily load balanced (with director sticking users to the > >>> same dovecot backend) > >>> > >>> On the upcoming upgrade we intent to: > >>> - upgrade ceph to 12.X (Luminous) > >>> - drop the SSD Cache Tier (because it's deprecated) > >>> - use bluestore engine > >>> > >>> I was said on freenode/#dovecot that there are many cases where SDBOX > >> would > >>> perform better with NFS sharing. > >>> In case of cephfs, at first, I wouldn't think that would be true > because > >>> more files == more generated IO, but thinking about what I said in the > >>> beginning regarding sdbox vs mdbox that could be wrong. > >>> > >>> Any thoughts will be highlt appreciated. > >>> > >>> Regards, > >>> > >>> Webert Lima > >>> DevOps Engineer at MAV Tecnologia > >>> *Belo Horizonte - Brasil* > >>> *IRC NICK - WebertRLZ* > >>> > >>> > >>> > >>> _______________________________________________ > >>> ceph-users mailing list > >>> ceph-users(a)lists.ceph.com > >>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > >>> > >> > >> _______________________________________________ > >> ceph-users mailing list > >> ceph-users(a)lists.ceph.com > >> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com > >> > > > >

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Re: Dovecot User Listing Error - getpwent() failed: Invalid Argument
by Reuben Farrelly 04 Oct '18

04 Oct '18

Sure: https://www.reub.net/files/dovecot/lightning-dovecot.conf https://www.reub.net/files/dovecot/thunderstorm-dovecot.conf Updated nightly. Reuben On 1/09/2018 12:26 am, Aki Tuomi wrote: > Can you provide doveconf -n? > > > > --- > Aki Tuomi > Dovecot oy > > -------- Original message -------- > From: Reuben Farrelly <reuben-dovecot(a)reub.net> > Date: 31/08/2018 17:12 (GMT+02:00) > To: Aki Tuomi <aki.tuomi(a)dovecot.fi>, Dovecot Mailing List > <dovecot(a)dovecot.org> > Subject: Re: Dovecot User Listing Error - getpwent() failed: Invalid > Argument > > No. Neither of those are installed on either system. > > Reuben > > On 1/09/2018 12:09 am, Aki Tuomi wrote: > > Could apparmor or selinux be causing this! > > > > > > > > --- > > Aki Tuomi > > Dovecot oy > > > > -------- Original message -------- > > From: Reuben Farrelly <reuben-dovecot(a)reub.net> > > Date: 31/08/2018 16:50 (GMT+02:00) > > To: Dovecot Mailing List <dovecot(a)dovecot.org> > > Subject: Dovecot User Listing Error - getpwent() failed: Invalid Argument > > > > Hi, > > > > I'm running dovecot-2.3 git and seeing on 2 of my Dovecot installations, > > the following message logged quite frequently: > > > > Aug 31 16:55:53 lightning.reub.net dovecot[7698]: auth-worker(7707): > > Error: getpwent() failed: Invalid argument > > Aug 31 16:55:53 lightning.reub.net dovecot[7698]: replicator: Error: > > User listing returned failure > > Aug 31 16:55:53 lightning.reub.net dovecot[7698]: replicator: Error: > > listing users failed, can't replicate existing data > > > > It appears that this could be having an effect on replication, but it's > > unclear because the secondary/replica doesn't see much traffic. > > > > Authentication is via PAM and the system is Gentoo Linux x86_64. passb > > driver = pam, userdb driver = static . > > > > doveadm user -u '*' shows the system users listed twice like this (is > > this a problem?) and then prints: > > > > ---- > > reuben > > liam > > reuben > > liam > > <some other users> > > Error: User listing returned failure > > Fatal: user listing failed > > ---- > > > > To me that doesn't look right. > > > > Can anyone suggest what could be causing this? I don't recall seeing > > this message some time ago so I suspect it's a recent change in either > > dovecot, or pam or glibc etc.. > > > > Thanks, > > Reuben

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Authenticate users using their firstname
by Fady AL HAYALI 04 Oct '18

04 Oct '18

Hi, I'm setting up a Postfic and Dovecot with LDAP email server. My users in LDAP is like this: dn: uid=firstname,ou=People,dc=domain,dc=com uid: firstname uidNumber: 4025 gidNumber: 4025 givenName: firstname objectClass: top objectClass: person objectClass: posixAccount objectClass: shadowAccount objectClass: organizationalPerson objectClass: inetOrgPerson loginShell: /bin/bash homeDirectory: /home/firstname cn: firstname lastname mail: firstname.lastname(a)domain.com<mailto:firstname.lastname@domain.com> This is how I connect Dovecot with LDAP hosts = ldapserver ldap_version = 3 base = ou=People,dc=domain,dc=com deref = never scope = subtree user_attrs = user_filter = (&(objectclass=inetOrgPerson)(uid=%n) pass_attrs = uid=user,userPassword=password pass_filter = (&(objectclass=inetOrgPerson)(uid=%n)) default_pass_scheme = SSHA When I enter a user's email address and password as the following: email: firstname.lastname(a)domain.com<mailto:firstname.lastname@domain.com> password: password and according to my setting which I used "%n" as you see above, the username used to authenticate is "firstname.lastname". I checked the Dovecot variables but I couldn't find something useful in this case to manipulate the "%n" variable. I would like to keep using email addresses as "firstname.lastname(a)domain.com"<mailto:firstname.lastname@domain.com> but authenticate users using their first name. I really hit a wall here and any help will be much appreciated.

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Possible architecture ?
by Alexandre Ellert 03 Oct '18

03 Oct '18

Hi, I'd like to achieve the following setup whit dovecot using multiple servers : - one server dedicated to all client IMAP (TLS) connections (i <http://mail.numeezy.com>map.mymaindomain.com, see below ) - each backend server has it's own local storage. no replication - each backend server responsible of a few domains - each backend server has it's own Mysql local database for user's passwords. ===> Server 1 : domains A, B and C ====> i <http://mail.numeezy.com>map.mymaindomain.com ===> Server 2 : domains D, E and F (143 TLS / 993 SSL) ===> Server 3 : domains G, H For example, if a user connects from domain E to i <http://mail.numeezy.com> map.mymaindomain.com, will Dovecot be able to use password database hosted on Server 2 ? Thank you ! Alex

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Bug in conditionals to assign values to variables?
by Angel L. Mateo 02 Oct '18

02 Oct '18

Hi, According to https://wiki2.dovecot.org/Variables you could use conditionals to assign values to a varible. The syntax is: %{if;value1;operator;value2;value-if-true;value-if-false} where any of the fields can refer to another field using %v or %{value} syntax. The problem is that when I use a config like: user_attrs = ...,=relpath=%{if;%u;eq;somevalue;valuetrue;valuefalse} it works without any problem. But when I use: user_attrs = ...,=relpath=%{if;%{user};eq;somevalue;valuetrue;valuefalse} then it reports in logs: Sep 28 14:23:22 myotis60 dovecot: auth: Error: var_expand_long(if;%{user}) failed: if: requires four or five parameters, got 1 anyway, the variable is correctly initialized, but I get the log. Is this a bug? PS: I'm running dovecot 2.2.33 -- Angel L. Mateo Martínez Sección de Telemática Área de Tecnologías de la Información y las Comunicaciones Aplicadas (ATICA) http://www.um.es/atica Tfo: 868889150 Fax: 868888337

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split auth from other logging
by Kai Schaetzl 02 Oct '18

02 Oct '18

Is there a way to split the auth logging (logins and failed logins) from the other logging that goes to info_log_path = /var/log/dovecot/dovecot.log ? This log gets a lot of other info as well, most notably the lmtp notifications about every filed mail (with no level stamping, btw). This makes it really hard to find authentication errors quickly and comfortably. It would be nice to be able to split at least the lmtp messages away. Kai

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v2.3.3 rc1 - Error: sieve: !!BUG!!: Binary compiled from dovecot.sieve is still corrupt
by James 01 Oct '18

01 Oct '18

I have a sieve problem with dovecot v2.3.3 rc1 with either of pigeonhole 0.5.2 or 0.5.3.rc1. The the change that triggers this is in dovecot not pigeonhole. Sieve filtering has been working with v2.3.2 and many earlier versions. Log report: Sep 24 10:36:13 mailhost dovecot: [ID 702911 mail.error] lmtp(user(a)domain.tld)<15816><RnikKw2wqFvIPQAAs831Jw>: Error: sieve: !!BUG!!: Binary compiled from /path/to/domain/user/dovecot.sieve is still corrupt; bailing out and reverting to default delivery This is a sieve script with a vacation handler. My other sieve filters are working. My actual sieve filter worked before and was written by Roundcube web mail. My failing test script is cut-n-paste from the sieve examples https://wiki2.dovecot.org/Pigeonhole/Sieve/Examples so should not be in doubt. The text script compiles to dovecot.svbin and newly compiled files are identical to older versions, the compilation has not changed. James.

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doveadm backup abort in imapc-client.c
by Evan Klitzke 01 Oct '18

01 Oct '18

I am using Dovecot 2.2.36 and I am trying to use doveadm backup to migrate email from Gmail to Dovecot. When I run doveadm backup, it goes for a while and then eventually hits an assertion error (I've tried this a few times now and it happens reliably). The assertion failure looks like this: dsync(evan(a)eklitzke.org): Panic: file imapc-client.c: line 179 (imapc_client_run_pre): assertion failed: (client->ioloop == NULL) The last few lines of log output before the crash look like this: https://gist.github.com/eklitzke/9a0dd77c44a6ee33e812f85d5773c24c The GDB backtrace when the program panics looks like this: https://gist.github.com/eklitzke/6b311474b08b546c462e0444c5cf479b The output of "dovecot --version" prints "2.2.36 (1f10bfa63)" and I'm using the version provided by Fedora's dovecot-2.2.36-1.fc28.src.rpm package. Is there any other information I can provide to assist in debugging? I could provide a core dump provided there was a way to scrub my IMAP credentials. -- Evan Klitzke pgp: 0x157EFCACBC648422 e: evan(a)eklitzke.org w: https://eklitzke.org

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