February 2010 - dovecot

[Dovecot] Highly Performance and Availability
by Wayne Thursby 22 Feb '10

22 Feb '10

Hello everyone, I am currently running Dovecot as a high performance solution to a particular kind of problem. My userbase is small, but it murders email servers. The volume is moderate, but message retention requirements are stringent, to put it nicely. Many users receive a high volume of email traffic, but want to keep every message, and *search* them. This produces mail accounts up to 14+GiB. After seeing the failures of my predecessors, I transitioned to Postfix/Dovecot and haven't looked back. Things are running nicely with the below setup. Postfix and Dovecot running on the same virtual machine on a Dell 2950 with 1x Xeon E5440 on ESXi 4. Maildirs served up by 10x146GB 15k RPM SAS drives on RAID-10 via direct attached Dell MD-1000. We are transitioning other services to high availability, and I'm wondering exactly how to provide some kind of near-realtime failover for my Postfix/Dovecot machine. The MD-1000 provides nothing in the way of iSCSI, but it *does* have two SAS connections available, only one of which is in use. I have been looking at the Dell EqualLogic stuff and it seems to provide what we need. I can get most of the information I need from the rep, but I wonder if anyone has any experience with high performance requirements on these kinds of storage. I'd like to continue running my current hardware as the primary mail server, but provide some kind of failover using the SAN. The primary usage of the SAN will be to make our 2TB document store highly available. I'm wondering what kind of options I might have in the way of piggybacking some email failover on this kind of hardware without sacrificing the performance I'm currently enjoying. Is it possible to go with a virtual machine mounted on iSCSI acting as a backup mail server? How would I sync the two, NBD+MD? Any experience doing this with maildirs? I wonder about the performance. Can it be as simple as attaching my MD-1000's second controller to the SAN magic box via SAS and pressing the Easy button? Is it as expensive as running my primary mailserver mounted from the SAN via Fiber Channel? Will that get me under 30ms latency? I welcome any suggestions the group may have. -- Wayne Thursby System Administrator Physicians Group, LLC

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[Dovecot] Best inode_ratio for maildir++ on ext4
by Rodolfo Gonzalez 22 Feb '10

22 Feb '10

Hi, This might be a silly question: which would be the best inode ratio for a 5 Tb filesystem dedicated to Maildir++ storage? I use ubuntu server, which has a preconfigured setting for mkfs.ext4 called "news" with inode_ratio = 4096, and after formating the fs with that setting and then with the defautl setting I see this difference of space (wasted space, but more inodes): 4328633696 free 1K-blocks with mkfs's "-T news" switch = 1219493877 free inodes 4557288800 free 1K-blocks with default mkfs settings = 304873461 free inodes I'll be storing e-mail messages for around 20,000 accounts on that partition (average 512 Mb per account). Would you consider worth the waste of about 200 Gb of the filesystem space in exchange of more inodes? Thanks. Rodolfo.

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[Dovecot] Dovecot setting up SASL/TLS now it will not start
by VaineDragon 22 Feb '10

22 Feb '10

[root@dragon-server dragon]# /etc/init.d/dovecot restart Stopping Dovecot Imap: [FAILED] Starting Dovecot Imap: Error: Error in configuration file /etc/dovecot.conf line 795: Unknown section type (section changed in /etc/dovecot.conf at line 787) Fatal: Invalid configuration in /etc/dovecot.conf Any help will be greatly appreciated. -- View this message in context: http://old.nabble.com/Dovecot-setting-up-SASL-TLS-now-it-will-not-start-tp2… Sent from the Dovecot mailing list archive at Nabble.com.

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[Dovecot] enabling IMAP SORT and THREAD extensions
by Colin Brace 21 Feb '10

21 Feb '10

Hi all, The home page of the Dovecot website indicates: "Supports multiple commonly used IMAP extensions, including SORT, THREAD and IDLE." However, I cannot find instructions in the Wiki for how to enable these extensions. Can someone tell me how to do this? I will add this info to the Wiki myself if need be. Thanks. ----- Colin Brace Amsterdam http://lim.nl -- View this message in context: http://old.nabble.com/enabling-IMAP-SORT-and--THREAD-extensions-tp27673898p… Sent from the Dovecot mailing list archive at Nabble.com.

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Re: [Dovecot] Bug#570764: dovecot-common: sieve should allow Return-path header for address test
by Marco Nenciarini 21 Feb '10

21 Feb '10

package dovecot-common forward 570764 dovecot(a)dovecot.org thanks Martin Schwenke ha scritto: > Package: dovecot-common > Version: 1:1.2.10-1 > Severity: normal > > > I attempt to compile the following sieve script... > > martins@bilbo:~/tmp$ cat test.sieve > if address :is "Return-path" "owner-cipe-l(a)inka.de" { > keep; > } > > [Yes, it is useless - a minimal example to illustrate the bug. :-) ] > > ... and I get the following error: > > martins@bilbo:~/tmp$ sievec test.sieve > test: line 1: error: specified header 'Return-path' is not allowed for the address test. > test: error: validation failed. > Error: failed to compile sieve script 'test.sieve' > > This test is included in an example in the Dovecot sieve documentation at: > > http://wiki.dovecot.org/LDA/Sieve#Mail_filtering_by_various_headers > > That seems to suggest that it should work! > > peace & happiness, > martin > > -- System Information: > Debian Release: squeeze/sid > APT prefers testing > APT policy: (990, 'testing') > Architecture: amd64 (x86_64) > > Kernel: Linux 2.6.26-2-amd64 (SMP w/4 CPU cores) > Locale: LANG=en_AU.UTF-8, LC_CTYPE=en_AU.UTF-8 (charmap=UTF-8) > Shell: /bin/sh linked to /bin/bash > > Versions of packages dovecot-common depends on: > ii adduser 3.112 add and remove users and groups > ii libbz2-1.0 1.0.5-4 high-quality block-sorting file co > ii libc6 2.10.2-2 GNU C Library: Shared libraries > ii libcomerr2 1.41.9-1 common error description library > ii libdb4.8 4.8.26-1 Berkeley v4.8 Database Libraries [ > ii libgssapi-krb5-2 1.8+dfsg~alpha1-5 MIT Kerberos runtime libraries - k > ii libk5crypto3 1.8+dfsg~alpha1-5 MIT Kerberos runtime libraries - C > ii libkrb5-3 1.8+dfsg~alpha1-5 MIT Kerberos runtime libraries > ii libldap-2.4-2 2.4.17-2.1 OpenLDAP libraries > ii libmysqlclient16 5.1.41-3 MySQL database client library > ii libpam-runtime 1.1.1-1 Runtime support for the PAM librar > ii libpam0g 1.1.1-1 Pluggable Authentication Modules l > ii libpq5 8.4.2-2 PostgreSQL C client library > ii libsqlite3-0 3.6.22-1 SQLite 3 shared library > ii libssl0.9.8 0.9.8k-8 SSL shared libraries > ii openssl 0.9.8k-8 Secure Socket Layer (SSL) binary a > ii ucf 3.0025 Update Configuration File: preserv > ii zlib1g 1:1.2.3.4.dfsg-3 compression library - runtime > > dovecot-common recommends no packages. > > Versions of packages dovecot-common suggests: > ii ntp 1:4.2.4p8+dfsg-1 Network Time Protocol daemon and u > > -- no debconf information > > This bug happen with latest version of sieve patches applied on dovecot 1.2.10. Regards, Marco -- --------------------------------------------------------------------- | Marco Nenciarini | Debian/GNU Linux Developer - Plug Member | | mnencia(a)prato.linux.it | http://www.prato.linux.it/~mnencia | --------------------------------------------------------------------- Key fingerprint = FED9 69C7 9E67 21F5 7D95 5270 6864 730D F095 E5E4

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[Dovecot] Dovecot blog
by Timo Sirainen 20 Feb '10

20 Feb '10

http://blog.dovecot.org/ I was thinking that I could blog about: - ideas for new Dovecot feature designs - when I actually manage to implement some new great feature - maybe some stuff about IMAP/email in general - and maybe whenever I happen to be moving to a different country I wasn't really planning on announcing new releases there. Dovecot feature designs are also sent to Dovecot mailing list, as before. But there have been other things I've thought about mentioning somewhere, but Dovecot ML didn't really seem like the right place. I doubt I'll update the blog very often. But that probably makes it even more useful, since casual readers find the useful stuff quickly. :)

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[Dovecot] Virtual POP3 Inbox question
by Josephus 20 Feb '10

20 Feb '10

Hi, I'm having trouble implementing the virtual pop3 inbox solution in Dovecot 1.2.x. As the following wiki page describes (http://wiki.dovecot.org/Plugins/Virtual) one should only set the inbox=yes flag for the virtual namespace which then flattens all mailboxes in the realmails/ prefix. In the above example when I set the inbox=yes flag for the virtual namespace, the inbox in the realmails/ prefix gets left out for obvious reasons. How did the original author intend this to work? Regards, Jos

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[Dovecot] Dovecot design-question
by Werner 20 Feb '10

20 Feb '10

Hi everybody, we're currently in the process of drafting our new mailserver-setup. Instead of a single-server-setup we'd like to have two equal servers behind a loadbalancer like LVS and shared mailhomes on NFS. We'd like to use dovecot for POP/IMAP, dovecot-deliver as LDA. - It's probably the best idea to direct SMTP and POP/IMAP always to the same server behind the loadbalancer (because dovecot-deliver is used which updates indexes?) - If we think of a "active/passive" setup: dovecot index-files locally or on the nfs-share? - Is it possible to activate loadbalancing for SMTP in this environment if dovecot index-files are held locally on each machine (POP/IMAP is directed only to one of the two servers?) Any comments welcome :-) Werner

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[Dovecot] exporting client socket to postfix
by zhong ming wu 20 Feb '10

20 Feb '10

Dear List, I have a few questions regarding dovecot sasl authentication that are somewhat related to each other. I have a working dovecot config with ---------- ssl_verify_client_cert = yes .. . ssl_require_client_cert = yes ssl_username_from_cert = yes --------------- (With this set up I need not set a correct user name in my mail client so long as I have it correctly in cert.) It turns out that I cannot export client socket to postfix to do smtp authentication unless I comment out ssl_require_client_cert=yes Does it mean that postfix is not passing to dovecot any information about certificate? Is passing certificate information not part of sasl framework? If so I won't be able to use it with a different sasl implementation. Also if I comment out ssl_require_client_cert=yes, then I can no longer use username from cert to log in to retrieve my pop mail. I prefer to get username this way otherwise my thunderbird mailbox reads user@domain.org@domain.org; I could have more than one domain in my dovecot servers. Thanks mr.wu

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[Dovecot] passing parameters to deliver
by kjonca＠wp.pl 20 Feb '10

20 Feb '10

Is any posibility to pass parameters/environment variables to deliver with sieve plugin? I have some procmail rules to decide where mail should go, which can't be migrated to sieve (uses external programs). So far I write it to maildirs, but I wonder to migrate to mdbox, and procmail can't handle it. Any ideas? KJ -- http://modnebzdury.wordpress.com/2009/10/01/niewiarygodny-list-prof-majewsk… można nie mieć nawet żadnego sensownego argumentu, a dzięki odpowiedniej gestykulacji stworzyć poczucie wiarygodności. Puls Biznesu

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