- dovecot - dovecot.org

How to understand NFS lookup (requests) spike?
by Alessio Cecchi 17 Feb '16

17 Feb '16

Hi, I'm are running a classic Dovecot setup: About ten thousand connected users mailbox in Maildir format shared via NFS (NetApp) Director for POP/IMAP Delivery via Dovecot LDA All works fine but sometimes I see a spike on the load of POP/IMAP servers and high disk usage (close to 100%) on NFS NetApp. When this happens on NFS stats (of POP/IMAP) I can see an high volume of "lookup, remove, rename" requests. Example (avg is during normal load, max is request number during the spike): Lookup avg 100 max 700 Remove avg 50 max 300 Rename avg 50 max 300 Getattr avg 200 max 250 Total NFS avg 600 max 1800 I think that some users are doing some kinds of "intensive" operations on their mailbox but what and who? I am currently using "iotop" to monitor the activity of individual users but I can't figure out who is causing the high number of I/O requests. Have you any suggestions? Thanks -- Alessio Cecchi Postmaster @ http://www.qboxmail.it https://www.linkedin.com/in/alessice

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sieve: store string list in varable
by whats_up＠gmx.net 16 Feb '16

16 Feb '16

Hi, I'm working on a Sieve script and want to store a list of addresses in a variable to easily access the list multiple times later. For example I want to transform this: if address :is "from" ["daffy.duck(a)example.com", "porky.pig(a)example.com", "speedy.gonzales(a)example.com"] { fileinto "friends"; } into something like this: require ["fileinto", "variables"]; set "friends" ["daffy.duck(a)example.com", "porky.pig(a)example.com", "speedy.gonzales(a)example.com"] if address :is "from" $friends { fileinto "friends"; } Any ideas on this? regards Knut

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more than 6000 subfolders in the same level
by Chris 16 Feb '16

16 Feb '16

Dear All, I'm going to use a public namespace with more than 6000 folders and subfolders. On the local ext4-filesystem the nested IMAP subfolders will all be in the same directory: /var/vmail/public/folder1 /var/vmail/public/folder1.subfolder1a /var/vmail/public/folder1.subfolder1b ... Is this possible without any performance issues? Would it be better to use "real" subfolders with / as separator? Is / separator for public namespace and . for private namespace possible? - Chris

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the prefix number of the configuration filename
by Dogz 16 Feb '16

16 Feb '16

Hi all, I am very curious about the prefix number of the configuration filename, such as 10-auth.conf 10-director.conf 10-logging.conf 10-mail.conf 10-master.conf 10-ssl.conf 15-lda.conf 15-mailboxes.conf 20-imap.conf 20-lmtp.conf 20-managesieve.conf 20-pop3.conf 90-acl.conf 90-plugin.conf 90-quota.conf 90-sieve.conf 90-sieve-extprograms.conf What are those meanings of 10,15,20 and 90 ? Please advise me and thank you in advance. -- Best Regards, Dogz

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Accessing to mail as another user
by Angel L. Mateo 16 Feb '16

16 Feb '16

Hello, I'm looking for a way to access to a POP/IMAP account as another user different than me, but using my password. That is, I'm "someone(a)domain.com" and I want to access to "anotherone(a)domain.com" mailbox using the password of "someone(a)domain.com", not the "anotherone(a)domain.com" (something similar to master passwords, but without sharing any password). Obviously, in my LDAP backend I can configure something to authorize "someone" to access to "anotherone"'s mailbox. At this momment, I'm trying to use someone@domain.com@anotherone@domain.com as username, with a passdb that uses %{username}@%{domain_first} to authenticate the user, but I'm having problem to configure a userdb map to get the mailbox, because the %{domain_first} variable returns just "domain.com". To fix this, I could use "someone@anotherone@domain.com", but this has problems with virtual domains an different users with same username (someone(a)domain.com and someone(a)otherdomain.com) Looking at documentation, at [1], in the "auth_user" variable says: "... If username changes during authentication, this value contains the original username..." what leads me to think that there is some way to change the user during the authentication process, but I don't know how or maybe I'm assuming wrong. Any help with this? Thank you [1] http://wiki.dovecot.org/Variables -- Angel L. Mateo Martínez Sección de Telemática Área de Tecnologías de la Información y las Comunicaciones Aplicadas (ATICA) http://www.um.es/atica Tfo: 868887590 Fax: 868888337

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Pigeonhole and duplicate checking
by Dan Ragle 15 Feb '16

15 Feb '16

I spent some time setting up Dovecot LMTP with Pigeonhole this weekend. I got most of the things I wanted to working but have a few issues that I'm hoping that someone might be able to help with. First, I'm running the stock version of the tools from the core repos for CentOS/6, which means Dovecot 2.0.9 and Pigeonhole 0.2.2. Unfortunately, I don't expect to be able to upgrade those anytime soon, so I'm hoping I can find workarounds for my existing versions. My mailserver is sendmail, I linked to Dovecot LMTP by adding: FEATURE(`local_lmtp', `[IPC]', `FILE /var/run/dovecot/lmtp')dnl to my sendmail.mc. In my prior procmail setup, I auto-forwarded all my SPAM E-mail to a separate user on the system with their own account (called spamuser). In the Pigeonhole setup it looks like I have to redirect those messages (i.e., redirect "spamuser(a)mydomain.com";). That works, but I'm having issues with "duplicate" messages getting delivered directly to my inbox instead of getting redirected. IOW, my regular user's .dovecot.sieve has: if header :contains "X-Spam-Flag" "YES" { redirect "spamuser(a)mydomain.com"; stop; } and the spamuser's .dovecot.sieve has: require ["imap4flags"]; setflag "\\seen"; (this system is entirely for personal use, no concerns with a user's Spam being seen via the separate spamuser account). Now, the problem I'm having is that sometimes a message arrives with a duplicate message-ID. Here's an abbreviated example from my maillog: Feb 15 00:30:46 myhost sendmail[26844]: u1F5UeBP026844: from=<ciuehazt(a)autoonecareers.com>, size=613, class=0, nrcpts=1, msgid=<68895654496651-HLTYGGRLPDJDVTZRHFIKGAON(a)hverovvxzb.arkansas-email.com>, proto=SMTP, daemon=MTA, relay=117.27.191.61.broad.static.hf.ah.cndata.com [61.191.27.117] (may be forged) Feb 15 00:31:05 myhost dovecot: lmtp(26856): Connect from local Feb 15 00:31:07 myhost sendmail[26867]: u1F5UvFi026867: from=<ciuehazt(a)autoonecareers.com>, size=613, class=0, nrcpts=1, msgid=<68895654496651-HLTYGGRLPDJDVTZRHFIKGAON(a)hverovvxzb.arkansas-email.com>, proto=SMTP, daemon=MTA, relay=117.27.191.61.broad.static.hf.ah.cndata.com [61.191.27.117] (may be forged) Feb 15 00:31:10 myhost dovecot: lmtp(26856, dmr): 7Hj/LoBiwVboaAAACXJZQA: sieve: msgid=<68895654496651-HLTYGGRLPDJDVTZRHFIKGAON(a)hverovvxzb.arkansas-email.com>: forwarded to <spamuser(a)mydomain.com> Feb 15 00:31:10 myhost dovecot: lmtp(26856): Disconnect from local: Client quit Feb 15 00:31:10 myhost dovecot: lmtp(26893): Connect from local Feb 15 00:31:10 myhost dovecot: lmtp(26893, spamuser): 9TPnN55iwVYNaQAACXJZQA: sieve: msgid=<68895654496651-HLTYGGRLPDJDVTZRHFIKGAON(a)hverovvxzb.arkansas-email.com>: stored mail into mailbox 'INBOX' Feb 15 00:31:11 myhost dovecot: lmtp(26893): Disconnect from local: Client quit Feb 15 00:31:18 myhost dovecot: lmtp(26893): Connect from local Feb 15 00:31:18 myhost dovecot: lmtp(26893, dmr): +TPnN55iwVYNaQAACXJZQA: sieve: msgid=<68895654496651-HLTYGGRLPDJDVTZRHFIKGAON(a)hverovvxzb.arkansas-email.com>: discarded duplicate forward to <spamuser(a)biblestuph.com> Feb 15 00:31:18 myhost dovecot: lmtp(26893, dmr): +TPnN55iwVYNaQAACXJZQA: sieve: msgid=<68895654496651-HLTYGGRLPDJDVTZRHFIKGAON(a)hverovvxzb.arkansas-email.com>: stored mail into mailbox 'INBOX' So the first message comes in and is redirected properly to my spamuser and stored in the inbox. The second one comes in, pigeonhole sees it's a duplicate, refuses to redirect it, and stores it in my inbox instead. I tried forcing the .dovecot.lda-dupes file to be a symlink to /dev/null just to see if it would work, but unfortunately dovecot just recreates it as a normal file the next time it delivers to that user. Ideally, I'd like to just discard the duplicates. It looks like there is duplicate testing functionality available, but not until later versions of Dovecot/Pigeonhole. Is there anyway I can either just discard the duplicates, or get them to be redirected to the spamuser? Also, some other questions I came up with along the way: Is there any way I can force a message to fileinto a different user's Mailbox? I'm guessing no since it appears that the lmtp drops root privileges before the global sieve script is interpreted, but thought I'd ask anyway. I did try: fileinto "/var/mail/spamuser"; But Dovecot complained, something about the mailbox pattern being invalid. If it were possible, I would think it would want something like fileinto "spamuser:INBOX"; instead, but I don't know if that is even possible. In a global sieve script, is there anyway to know/test which system user is the targeted user for delivery? So in a global sieve_before script I could test the target user, and if it's spamuser just file it immediately and stop with no further testing? Thanks for any assistance! Dan

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Health check for dsync?
by Rich Wales 15 Feb '16

15 Feb '16

I am syncing two Dovecot sites using dsync. Are there any tools available to confirm that dsync is (or is not) running properly between the two sites? (E.g., something I could run periodically in Nagios?) Rich Wales richw(a)richw.org

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Redundant and Geobalancing setup
by Cedric Malitte 15 Feb '16

15 Feb '16

Hi, I use dovecot for a long time now, but only as a single isolated server each time. I joined a company a few years back. We had trouble with compagnies hosting our mail, supposedly full redundant and so on. The company is small, but we have many dealers around the world, and it's growing. Mail became the fist choice for clients to contact the dealers. No mail, and we loose sales. For now we have a single server ( with a backup ) on east coast. And sometimes peoples from EU complain about speed.... ah users :) What I'd like to implement is a redundant system with 2 servers, one in NA, one in EU. And I'd also like to be able to add another server if needed on the west coast. Idea is, that if a server goes down, the users will be able to still receive and send mails, and never loose mails. For geobalacing and failover, I read that I can do it with DNS ( I'm with easydns ). I'm at the first stage where I collect informations that I try to understand and foresee a solution. First idea is to set up servers with a mysql master, slaves and a glusterfs in replica mode on the servers. I tried glusterfs on FreeBSD and OMG, it's slow as hell ! ( well maybe it's a trouble on the VMs nics ) On centos it's way better. But I read there might be trouble/index corruption for the mail storage on "shared" space using maildir. I also had a look at dsync, but I wonder if it can be used on more than 2 servers. I found many pages on dovecot clusters using shared storage NFS mounted, but I feel it's not really what I need as the servers will be in different datacenters. So any guide, clue hint would be really appreciated for me to do my homework ! Regards. Cedric

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Re: Question on setting up dovecot
by Jeffery Small 14 Feb '16

14 Feb '16

The problem is solved! A great thanks to everyone for all the valuable information and suggestions you offered. I learned quite a bit, especially about talking to the dovecot server using the telnet/openssl suggestions and the available POP3 commands. Many of you were correct about your diagnosis, but I had some things happening that were creating confusion. Here is a brief summary of what I discovered. There were a few initial dovecot configuration issues which I eventually ironed out and, as I was reporting at the end of last week, the diagnostic logs seemed to indicate that the connection was successful. Yes, it turned out that Outlook was indeed set to leave a copy of the emails on the server for two weeks -- a setting hidden away on a sub-menu. Now, why this did not seem to be the case was because every time Outlook connected to the Solaris system to retrieve mail, all the messages were immediately deleted (despite this setting), so I was expecting the same behavior on the Linux machine and wasn't looking for the setting. There is something different about how the pop3 handler is working on the two systems. The second problem, which some of you guessed, was that the emails left on the server were not being downloaded because when I wasn't looking, Outlook had already downloaded and tagged them. So, even when I thought there was new mail (new to me anyway) in the inbox, Outlook had beaten me to them so that when I looked, I could see no new mail flowing over to the Windows machine. Disabling the retention setting removed the ambiguity and now I see any new mail in the inbox moving to the other system. Thanks again to everyone! -- Jeff

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ANNOTATE plugin? Squirrel uses it for EXPIRATION information
by Heiko Schlittermann 14 Feb '16

14 Feb '16

Hi, it seems that Squirrel mail uses Mailbox annotations for storing Expire times on the Server. It's an Cyrus server currently. (I've no clue how cyrexpire is able to read it's information from the annotiations) Does dovecot support some similiar mechanism? Or - does anybody know anything about how it's supposed to work on Cyrus and how it can be emulated/simulated with dovecot? Thanks in advance, Best regards from Dresden/Germany Viele Grüße aus Dresden Heiko Schlittermann -- SCHLITTERMANN.de ---------------------------- internet & unix support - Heiko Schlittermann, Dipl.-Ing. (TU) - {fon,fax}: +49.351.802998{1,3} - gnupg encrypted messages are welcome --------------- key ID: F69376CE - ! key id 7CBF764A and 972EAC9F are revoked since 2015-01 ------------ -

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