Experiences with Mail servers

[Jason Dixon]

On Dec 5, 2004, at 9:21 AM, Chris Mason wrote:

> I'm looking for feedback on experiences of implementing an enterprise 
> mail
> server with IMAP and webmail, preferably groupware, on our Dual Xeon 
> Fedora
> server. We currently have sendmail, uw-imap, squirrelmail, in standard
> Redhat configuration, and we are having huge load problems as the 
> present
> setup is not capable of supporting the needs of our users. Large mail
> folders bring the server to it's knees. We only have 25 users but they
> travel and use the mail system as a filing system, routinely saving 
> 10MB
> emails and never cleaning up old mail.

I have a hard time categorizing 25 users as an Enterprise environment.  
If the current configuration is meeting your feature requirements, I 
would focus on where your performance bottleneck(s) lie.  There is no 
reason why the average colocated server (dual Xeon exceeds my 
definition of such) shouldn't be able to handle that load.  At first 
glance, it sounds like you might be running into the performance 
limitations of mbox.

What kind of testing have you done?  What size are you "large mail 
folders"?  Have you tried maildir instead?  I've been quite happy with 
Postfix/Courier servers, but I can't give you an accurate 
recommendation without a better idea of your current limitations.

> We also need more groupware type features such as file sharing, 
> messaging
> and calendaring. I am looking at Binari, Groupwise, Surgemail, and
> opengroupware which would involve more work to implement for me.

We've started looking at Open-Xchange 
(http://mirror.open-xchange.org/ox/EN/community/) for groupware 
solutions.  The demo is very impressive, and the price can't be beat.

--
Jason Dixon
DixonGroup Consulting
http://www.dixongroup.net