Your expectations from Dovecot in Plesk

[Nikolay.]

Please read this post thoroughly before posting your reply!

I'd like to ask community about their vision on Dovecot integration in Plesk. Think about this thread as a community wish-list for Dovecot secure IMAP/POP3 server.

In this thread please refrain from non-constructive comments such as:
1) "When will Dovecot be supported in Plesk?! I'm waiting since Plesk 10 for it!"
2) "I installed Dovecot with Roundcube and Sieve in under half an hour on my Plesk, so it shouldn't be that hard for Plesk developers."
3) "Dovecot and Courier are very similar, so replacing one with another should be really simple!"
4) "Dovecot must be added to Plesk 11.5."

Please post your thoughts on the best ways to integrate Dovecot with Plesk. It will be beneficial to provide sample use cases for features you describe. As well as explain why the feature is required (or not required). Be specific. If you have some experience with a given feature, please share it.

Here's an example (I don't have extensive experience with Dovecot, so bear with me):
"I'd like to have Sieve server-side mail filtering support in Dovecot. Nowadays customers are using IMAP on many mobile devices, often not powerful or capable enough to perform mail filtering on client side. It is also more convenient to set up mail filtering once on server-side instead of multiple times on different devices.
Sieve rules should be configurable via convenient web interface, e.g. via managesieve plugin for Roundcube webmail. Customer would log into his or her mail account via webmail and set up rules there."

The goal of this thread is to provide Plesk developers with additional information when the development starts. That way the chance of getting what we really need from Dovecot integration will be significantly increased.

For the record: Dovecot is an open source IMAP and POP3 email server for Linux systems, written with security primarily in mind. It's fast, simple to set up, requires no special administration and it uses very little memory. Think of it as a replacement to Courier-IMAP server. Primary feature of Dovecot differentiating it from Courier-IMAP is Sieve server-side mail filtering language support.

Support for Dovecot in Plesk was proposed several times on these forums.

 

[Nikolay.]

Let me start with my own expectations. I talked about Sieve support in the first post above, so in this post I'd rather first describe what I don't need.

1) POP3 before SMTP (aka SMTP after POP) - this is an outdated and insecure mechanism originally invented due to lack of authentication in SMTP. It should go away now, IMO, and save development time for other goodies.
2) Full text search support - this might be useful, but I don't see where I would actually use it.
3) Migrating settings from Courier-IMAP to Dovecot - while in theory this should be quite beneficial, I can't really expect it to work properly. So I would need to tune Dovecot settings after switching to it anyways. To be clear here by settings I mean small things like maximum number of connections and reusing Courier-IMAP SSL certificate or PCI compliance state. What I really need is Dovecot to start working right away after the switch. Other small problems could be fixed during small transition period manually.
4) QMail support and logging in with short mailnames (i.e., using only the part before '@') while using QMail - in my opinion QMail is heavily outdated. Anyway, I use Postfix, so I don't care about QMail at all.
5) Anything more complex in Panel itself than simple Dovecot service controls (start/stop/restart). If I need to I can configure Dovecot via shell.

Feel free to argue with these points if you disagree with me.

Here's what I need from Dovecot integration.

1) Sieve support as outlined in the first post.
2) Webmails (Horde and Roundcube) integration with Sieve management. Customers should be able to set up Sieve filters without leaving webmail software. Since I don't have much experience here, I can't really specify what kind of integration I expect. Please share your thoughts on this matter.
3) Ability to safely customize Dovecot configuration via shell (/etc/dovecot/conf.d/ would be enough, I suppose).
4) Working PCI compliance (via pci_compliance_resolver utility). Not sure about best settings though. If anybody has relevant experience, please advise.
5) Ability to switch back to Courier-IMAP in case of emergency. It should be as simple as with QMail-Postfix switch.
6) Good integration with other Plesk parts (this is obvious, I know), such as statistics collection (counting external POP3/IMAP traffic) and WatchDog extension (Dovecot service(s) monitoring).

I also invite you to comment on these points.

 

[Kartoffelsack]

Nice.

What I expect from dovecot (or better: what I know dovecot can do better than courier): it is way faster and more reliable. Especially having large IMAP-folders (many thousand mails per folder) it can decrease loading time significantly on same hardware. As I don't want to limit the number of mails my users may store in their folders, as well as I dont want to limit the size of the mails themselves, they now have to live with sometimes slow reaction from server. As dovecot uses its own database with metadata per account (which in case of corruption can be easily rebuilt) it can serve very large folders in fraction of seconds meanwhile courier has to read the whole directory structure which may take seconds or minutes, depending on size! And unlike courier which sometimes stumbles upon misleading configuration options (remember the problem with quota support and faulty generated entries which led to misfunction of courier?) dovecot is very fault-tolerant.

The other point is the already mentioned sieve-support. Before switching to new hardware and in same step to Plesk, we were using dovecot with sieve-support which gave our users the ability to have server-side filtering just in that moment the mail arrives. Not client-side filtering when opening the account, which also might take some time when a large number of mails has arrived and now has to be filtered. The combination of client-side filtering and slow reading of large folders is a pain for our users! Not talking about some convenient features sieve offers, like autoresponding and time-based filtering or responding which is impossible with client-side filtering mechanisms.

Of course the switch from courier to dovecot should be a matter of some clicks in Plesk, just as now the switch between postfix and qmail is. Additional configuration could be integrated in Plesk or be done directly on shell. As long as Plesk doesn't touch user generated config files this would be a good way too. But that's a requirement for all kind of user-generated configurations.

To be honest, I'm very unhappy that you guys at Parallels are now just beginning to start dovecot integration. This subject is on topic since years and again and yet again you told us you were working on integration, it would be in pipeline and be coming in some next release, but obviously you didn't do anything. You even didn't realize the need for some modern IMAP-server. Courier is as outdated as qmail is and holding on that software makes Plesk look some kind of outdated too, regardless what version number you pin on it.

 

[Nikolay.]

Thank you for (mostly) constructive and undoubtedly useful post, Kartoffelsack!

Before switching to new hardware and in same step to Plesk, we were using dovecot with sieve-support which gave our users the ability to have server-side filtering just in that moment the mail arrives.

How did your users manage Sieve filters before? Did you have special interface for that or did they just use shell?


It's sad no one else replied. I expected to see more people interested in Dovecot on these forums.

 

[Kartoffelsack]

How did your users manage Sieve filters before? Did you have special interface for that or did they just use shell?

We offered squirrelmail with sieve extension (avelsieve) as well as the ability to use client-side editing. In this case the user connected to managesieve on port 2000. For Thunderbird there is an add-on called "sieve" which offers a more or less simple interface for editing sieve rules. The squirrelmail extension is more convenient as it uses some kind of a wizard to build the rules but it only supports a subset of sieve capabilities. With the Thunderbird add-on one can use all functions of sieve but the user has to know the right syntax for it.

 

[Markus_Eyrich]

First and foremost, speed and server side mail filtering through sieve. I implemented dovecot with roundcube and sieve plugin manually here on some of our plesk servers and this works very well. Customers using servers with dovecot and roundcube/sieve are very happy that they can filter mail before it arrives the client. I would like to see this sieve filter management integrated into the plesk ui aswell as in roundcube (this is just a plugin so no real work for parallels).

 

[Nikolay.]

Thanks for you reply!

I implemented dovecot with roundcube and sieve plugin manually here on some of our plesk servers and this works very well.

Are you referring to the managesieve plugin?

I would like to see this sieve filter management integrated into the plesk ui aswell as in roundcube

Why do you think Sieve filters should be editable in Plesk UI? Maybe you can provide a sample use case?

 

[Markus_Eyrich]

I'm referring to this:

http://www.tehinterweb.co.uk/roundcube/#pisieverules

But i believe it's managesieve, if i look into my roundcube config it's a plugin called "sieverules" and this is very nice and functional.


As a use case for the Plesk UI:

Users can login into plesk with their accounts and can also manage their spam filter settings in Plesk, so why let them go to another location for the filters ? Also, as far as i know, Roundcube is actually the only webmail solution in plesk which supports "Sieve", didn't see anything like that in Horde. So if a domain uses Horde as webmail and sieve filters are not in the plesk ui, where should users edit those f

 

[sirhaplo]

Hi, i like this post.

I discovered Plesk only some months ago.
I used to self configure my servers with many and many piece of software working isolated each other (apache, dovecot, postfix, pure-ftp ... etc etc).

Plesk is a brilliant piece of sotware that simplified my life as sysadmin.

But i come from Dovecot ... its impossible to turn back ...
It's strange because Courier is at his end-of-life.

Sieve is a great tool, Dovecot is a must and Roundcube emerged like the best webmail ever.
I'd like to see this three actors works togheter in plesk.

But, i think that first of all we can help each other in write a simple tutorial on how to implement Dovecot inside Plesk 11 (or even 11.5).

I have no such abilities. I simply saw that courier base his authentication on a module "authpsa" that i imagine do the dirty work of checking the Plesk DB for us.
Anyone have ideas ?

 

[Sven L.]

2) Webmails (Horde and Roundcube) integration with Sieve management. Customers should be able to set up Sieve filters without leaving webmail software. Since I don't have much experience here, I can't really specify what kind of integration I expect. Please share your thoughts on this matter.

Can't really add anything apart from what has already been said, but +1 for what you said in the quote.

in fact, i wish customers would never have to leave the webmail interface for anything

 

[Nikolay.]

Thanks for the post, sirhaplo!

I discovered Plesk only some months ago.
I used to self configure my servers with many and many piece of software working isolated each other (apache, dovecot, postfix, pure-ftp ... etc etc).

Maybe you can share something about your use of Dovecot? Which features you used the most, did you make any significant changes in the default configuration and what for, did you integrate it with other software (e.g., Roundcube), etc.? In other words, do you expect anything specific from Dovecot in Plesk?

Can't really add anything apart from what has already been said, but +1 for what you said in the quote.

in fact, i wish customers would never have to leave the webmail interface for anything

Please note that I implied that I (personally) don't need Sieve management in Panel itself at all. Do you?


The rest of the post is off-topic:

But, i think that first of all we can help each other in write a simple tutorial on how to implement Dovecot inside Plesk 11 (or even 11.5).

I may share a few tips and tricks on how to use Dovecot with latest Plesk versions. But I'd rather not, since applying them will:
1) render your installation unsupportable and somewhat unstable and less secure;
2) most likely cause significant problems on future upgrades or updates.

Please also note that this thread is not about home-brew Dovecot support in Plesk.

 

[Sven L.]

Please note that I implied that I (personally) don't need Sieve management in Panel itself at all. Do you?

I would say no. Not for users anyways. There should be some admin options for me in the :8443 of course.
Did I give the impression I did need it? maybe I expressed myself wrong.
The more the users can do without ever leaving the roundcube interface, the better. I don't want them to need to go :8443 whatsoever


a bit of offtopic story here:

You see, nearly all my customers want webmail. And many of them used gmail in the past, where you do everything from one interface: mail, spam settings (white/black lists), personal filters and all of that does work serverside, meaning filters and everything else is applied even if you are using imap from your smartphone.
Those customers usually complain about the fact that they have to log into one interface for the webmail and separate interface for settings like auto-reply and black/white lists (the :8443 panel) and with horde it is even more confusing, because you can set a black/white list and filters in horde, but they only work when using the webmail as they are not serverside.

So, I would agree on everything that simplies this, to improve the end-user experience, which in the end will make me spend less time explaining things
I love roundcube since I met her (xD) and I already contacted parallels through this forums about several stuff regarding plugin compatibility which would make users able to:
- serverside auto reply settings from within roundcube interface
- serverside antispam/black/white list settings from within roundcube interface (seems like already planned to make work the sa_userprefs roundcube plugin, internal parallels ref.: TP131730)
- serverside filters settings from within roundcube interface (which, as I understand, would be possible with dovecot + sieve, right?)

plus, webmail has lots of languages for free, while :8443 panel needs to have extra license for more languages.

sorry for offtopic long story.

 

[Nikolay.]

Did I give the impression I did need it? maybe I expressed myself wrong.

No, of course not. I fully understand your concerns and reasoning. I just felt asking for clarification was to the point. And now we have something to talk about

- serverside filters settings from within roundcube interface (which, as I understand, would be possible with dovecot + sieve, right?)

Correct.

Not for users anyways. There should be some admin options for me in the :8443 of course.

What kind of admin options are you expecting in Panel? Please elaborate.

 

[hjt]

Technical neccessity to apply server-filter before autoresponder

Please post your thoughts on the best ways to integrate Dovecot with Plesk.

Hi!

Please excuse the late reply, but I was busy and this topic is around already for a while, so to me this is just another place where it is discussed.

Shortly speaking: I can go with dovecot or with cyrus, but going with courier is no more an option because of the lacking server side filtering. The problem is in today's internet reality: When you activate an autoresponder without filtering Spam and mailing lists first - on the server side - you can wait for max. one week and your server is in the list of spammers (because it replies to spam).

Sieve in this sense is an absolute technical must have. On the other hand it also is a very nice feature not to overload the mobile device inbox with messages you first want to collect on the server (mailing lists, newsletters etc.).

What I need:
- IMAP over SSL
- server side filtering, Sieve preferrably because it is supported by different web mailers
- SMPT over SSL
- I am not personally using it, but a web interface for mail which integrates a sieve filter editor should also be part of Plesk to make the feature accessible.
- full text search on server side would be a nice to have.
- User / mail account / mail alias management in Plesk admin interface (as it is the current status)

I personally use eGroupware for different purposes, including setting mail filters (on a non-plesk machine), and I would love to be able to use it on the Plesk server after dovecot (sieve) would be supported.


Might be skipped from my perspective:
- POP over SSL - I personally have not used it for a long time even the apps support IMAPS without producing too much traffic
- Pop before SMTP - all mail programs nowadays support passwords with SMTP
- anything not using SSL can be skipped

As a SMTP service, I prefer postfix over qmail due to ease of extendability (for spam detection, antivirus checking etc.), but qmail is told to be hardened (and difficult to extend / mis-use).

Thanks.

 

[Nikolay.]

Thanks for your reply, hjt!

Could you please elaborate about:

- full text search on server side would be a nice to have.

Why do you think it is needed? What kind of FTS engine should be used? What integration with other software you'd expect?

 

[hjt]

Hello Nikolai!

Why do you think it is needed?

Not saying that it is strongly needed, but it would be nice to support the use case of mobile devices which do not store all mails fully locally (because it would be beyont available storage). This feature is RFC 4731, which (as far as I know) is supported by dovecot. On mobile devices, to my knowledge, e.g the k9-mail app supports the search.

What kind of FTS engine should be used?

Available FTS plugins are explained here: http://wiki.dovecot.org/Plugins/FTS
Sorry, I do not have a personal experience on any other than the default coming with dovecot.

What integration with other software you'd expect?

As it is an RFC standard, no additional integration is required. maybe, a web mailer application would also use thie IMAP SEARCH command and should provide a mail search.

Thanks.

 

[Nikolay.]

Thanks, hjt. Got it!

FYI: Dovecot own search index (Squat) is obsoleted in Dovecot >= 2.1.

 

[Alex_G]

Hi Guys,
It is really a pity that PLESK do not come with built in DOVECOT support.
Currently I'am trying to get DOVECOT 2.2 running on PLESK 11.5 - but I'am struggling with the auth service.

Any ideas ?

Thanks in advance,
Alex

 

[Kirill K]

DOVECOT support is available since Plesk 11.6.4 You may try it!

From RN for 11.6.4 (http://download1.parallels.com/Ples...-11.6-linux-updates-release-notes.html#1164):
"Support for Dovecot. Panel now supports the Dovecot IMAP and POP3 mail server. Dovecot provides an interface for server-side mail management rules: filtering, sorting, auto-replies, and so on."

Guide from Plesk developers - http://devblog.plesk.com/2013/11/dovecot-in-plesk-for-linux-11-6/

 

[IgorG]

Dovecot support is available in the latest Plesk 12.0 preview.

You can download Plesk 12.0 from
https://sp.parallelsnetwork.com/parallels-plesk-panel-12-partner-preview/ (registration required)

Learn more about Dovecot support in our blog
http://devblog.plesk.com/2013/11/dovecot-in-plesk-for-linux-11-6/

Comment and discuss in our Forum
http://forum.parallels.com/showthread.php?294313-Plesk-12-0-Preview

We are looking for your feedback!