That's good to hear... I initially was using mbox as that was the 'default' set up, but then I realized I couldn't create sub-folders, so I converted to Maildir..

On 12/5/05, John Peacock jpeacock@rowman.com wrote:

wolff wrote:

...

Is there a size limit that dovecot can manage?

Maildir or mbox? Single folder or deep tree? It makes a big difference. We are using maildir and out of the 350 or so users we are using ~45GB total. dovecot can handle that and more.

John

-- John Peacock Director of Information Research and Technology Rowman & Littlefield Publishing Group 4501 Forbes Boulevard Suite H Lanham, MD 20706 301-459-3366 x.5010 fax 301-429-5748

Thanks for the info... I will check sendmail/procmail more to see if i can idenfity anything.

As far as tools or reports, I was thinking if I could look at the following things I could get a good idea of the status/health of my mailserver/imap server...

• The number of messages per date range, per user, received, delivered to each user mail box, and undeliverable messages
• The number of messages for unknown users or which had any sort of delivery problem
• Any error messages dovecot might produce communicating with the mta.

I guess the latter would be in my log files somewhere...I've found log entries identifying the starting/stopping of dovecot, but haven't come across any other messages (which I assume is a good thing and that the system is working just fine... and also because I am getting mail ...:-))

Regards,

Gary Wolff

On 12/5/05, Curtis Maloney cmaloney@cardgate.net wrote:

wolff wrote:

...

Hello,

I recently installed dovecot on a server running Debian.

I only have 10 users, but we probably have 6Gig of email between us.

We have only about 20 users, and store around 23 to 25G of mail. And that's mostly because I was tyrannical about people keeping their mailboxes lean until we got a new HDD :)

...

Things were working flawlessly for a couple of weeks, and I'm still getting email, but the last few days we are getting fewer emails that we typically do. So although things seem to be working well, everyone is suspicious something is wrong due to the lack of email volume.

Is there a size limit that dovecot can manage?

That's mostly dependent on your file system, since you're running Maildir. The limits will be on "messages per folder" and "single file size", both of which you are unlikely to have reached.

...

Are there any admin tools to get status messages for dovecot?

No, but that's not a bad idea. What sort of features would you be looking for?

...

Are there any reporting tools to show how many messages are processed/managed by dovecot?

Well, there are a few options and patches that make it easier to see how many messages people are reading with Dovecot... but since it's the _ingress_ of mail you're suspecting, I'd be looking at your MTA logs ( sendmail/postfix/qmail/exim/whatever ) -- if the MTA isn't seeing the mail, there's no way Dovecot can, either.

-- Curtis Maloney cmaloney@cardgate.net

Much of my aggravations with user use/misuse/stupidity traces back to this simple fact: there is rarely any feedback mechanism in server apps to indicate to the user the loads their practices cause. It is as if they were driving a car without a gas gauge, if they had bodies that didn't feel pain. /I/ wish that there was some metric that could tell a user the composite CPU and memory loads their mail usage represents. Of course, I'd also want the in-the-plans quota representation so that there is storage feedback as well. Will it work with the Berkely quota?

wolff wrote:

Thanks for the info... I will check sendmail/procmail more to see if i can idenfity anything.

As far as tools or reports, I was thinking if I could look at the following things I could get a good idea of the status/health of my mailserver/imap server...

• The number of messages per date range, per user, received, delivered to each user mail box, and undeliverable messages
• The number of messages for unknown users or which had any sort of delivery problem
• Any error messages dovecot might produce communicating with the mta.

I guess the latter would be in my log files somewhere...I've found log entries identifying the starting/stopping of dovecot, but haven't come across any other messages (which I assume is a good thing and that the system is working just fine... and also because I am getting mail ...:-))

Regards,

Gary Wolff

On 12/5/05, *Curtis Maloney* mailto:cmaloney@cardgate.net> wrote:

wolff wrote:
> Hello,
>
> I recently installed dovecot on a server running Debian.
>
> I only have 10 users, but we probably have 6Gig of email between us.

We have only about 20 users, and store around 23 to 25G of
mail.  And that's
mostly because I was tyrannical about people keeping their
mailboxes lean until
we got a new HDD :)

> Things were working flawlessly for a couple of weeks, and I'm
still getting
> email, but the last few days we are getting fewer emails that we
typically
> do.
> So although things seem to be working well, everyone is
suspicious something
> is wrong due to the lack of email volume.
>
> Is there a size limit that dovecot can manage?

That's mostly dependent on your file system, since you're running
Maildir.  The
limits will be on "messages per folder" and "single file size",
both of which
you are unlikely to have reached.

> Are there any admin tools to get status messages for dovecot?

No, but that's not a bad idea.  What sort of features would you be
looking for?

> Are there any reporting tools to show how many messages are
> processed/managed by dovecot?

Well, there are a few options and patches that make it easier to
see how many
messages people are reading with Dovecot... but since it's the
_ingress_ of mail
you're suspecting, I'd be looking at your MTA logs (
sendmail/postfix/qmail/exim/whatever ) -- if the MTA isn't seeing
the mail,
there's no way Dovecot can, either.

--
Curtis Maloney
cmaloney@cardgate.net <mailto:cmaloney@cardgate.net>

--

Stewart Dean, Unix System Admin, Henderson Computer Resources Center of Bard College, Annandale-on-Hudson, New York 12504
sdean@bard.edu voice: 845-758-7475, fax: 845-758-7035

Timo Sirainen wrote:

On Tue, 2005-12-06 at 08:02 -0500, Stewart Dean wrote:

...

Much of my aggravations with user use/misuse/stupidity traces back to this simple fact: there is rarely any feedback mechanism in server apps to indicate to the user the loads their practices cause. It is as if they were driving a car without a gas gauge, if they had bodies that didn't feel pain. /I/ wish that there was some metric that could tell a user the composite CPU and memory loads their mail usage represents.

Hmm. I'm not sure if such loads can be told to use in any easy way. But I've been thinking about having a plugin that could tell admin what's happening in the computer. What imap/pop3 processes are using all the disk I/O, memory and CPU and what exactly they're doing, and if there are some special conditions (eg. broken indexes causing the load, etc).

I've been using pacct/acctcom etc. on Solaris to give per-process CPU usage, disk block count, and kcore minutes. It's a bit fiddly though!

Talking of which, I've been trying IMAP SSL using both Perdition as a proxy to a Dovecot without SSL support, and Dovecot directly with SSL support and, to my surprise, found Dovecot-SSL using much more CPU for longer-lived processes (as much in an afternoon as my username usually uses in a week!). The Perdition proxy method seems to add a 30-50% overhead to the CPU load. I need to get some more users to test it all, though!

Best Wishes, Chris

-- --+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+- Christopher Wakelin, c.d.wakelin@reading.ac.uk IT Services Centre, The University of Reading, Tel: +44 (0)118 378 8439 Whiteknights, Reading, RG6 2AF, UK Fax: +44 (0)118 975 3094