Re: [exim] exim capabilities fo 10-30 K email accounts

I'm not a big fan of having all that on one box, though it does get more
difficult to manage services spread over several servers with cpanel (I
think).

For the email side, I think your server will probably do okay. Moving
spamassassin and clamav to a separate host will help a lot, as it is a lot
of cpu overhead.

Webmail (particularly squirrelmail) is pretty processor intensive, too.
If you have hundreds of simultaneous webmail users, I can definitely see
that being a problem. The individual user home pages aren't incredibly
resource intensive as a rule, but you do need to monitor them - you can
get one or two that becomes really popular and can cause the rest of your
system some problems.

Overall, the best way to approach the problem is to make your design
scalable. That way, you won't have a really big problem on your hands
when you exceed the capacity of the server(s) you've bought, and you're
not spending money needlessly at the beginning. If you would like to keep
it all on one server, then make sure that you would be able to add a
second or third server to spread the load. If you break things up by
function, make sure you can drop in multiple functional servers, like
spamassassin or webmail front end servers.

For that many accounts, I would also make sure you have a backup MX server
that can queue the mail up if your primary server(s) go down or get too
busy to accept new mail.

If cpanel has the ability to make changes across servers, I think that is
definitely the way to go.

I don't think this was exactly the answer you were looking for. System
design and capacity planning is definitely not a cut and dry, but can vary
widely based on the particular environment that you have. Ensuring your
system doesn't choke on day 1 due to load, and that you don't overspend on
hardware is a delicate balance.

Jerry

>
> Thanks Jerry! you rock :)
>
> Its for an ISP that will be running cPanel (and of course then Exim)
> so that means config is exim.conf and aliase/filter files, possible
> spamassassin, possible Neomail, Horde, Squirrelmail, possible clamav.
>
> Mostly it will be used for the 20-30 K DSL customers with one domain.
>
> With maybe a couple hundred DSL cuistomer type websites but nothing too
> dramatic or resource intensive.
>
> In your (or anyone's ;p) opinion would this be a good system to allow
> the description above to work efficiently?
>
> 2 Proc with good disk space for the project and 2GB ram?
>
> TIA :)
>
> Lee.M