Re: [exim] server specs

On Thu, 2010-06-17 at 09:52 -0400, Jean-Paul natola wrote:
> Hi all,
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> I'm trying get an idea of the hardware required for a new server, I currently use exim in th efollowing config
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> PIV 1.3
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> 1gig ram
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> 40 gig IDE drive
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> I use exim with spamassassin and clamav as a gateway to sanitze email that is then handed off to my exachange server.
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> Recently the 3 domains that are hosted have become increasingly popular targets fopr spam.
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> We only have ~75 users/boxes but have been getting hammered.
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> we get about 7000 legit emails per day
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Jean Paul,

I have spent some time working with Barracuda 'spam' firewalls which
have this (or a lower) specification and they can easily handle quite a
lot of work (hundreds of domains, thousands of messages). Inside they
are just a Linux box running a couple of MTA's, clamav, amavis-new,
apache and spamassassin. Some are only 512k and cope very well.

The trick is to reject as much bad mail as possible at the rcpt-to
stage. That is, drop bad IP addresses based on lists like Spamhaus &
Barracuda. Reject mail with missing or mismatched PTR records. Drop bad
'helo' like your own hostname or IP. Reject any spoofing of the 'mail
from'. Only mail getting past these checks should be offered to
Spamassassin to scan IMHO.

Some folk have Spamassassin set up to do all the network tests and it
can be a slow old bottleneck like that.

Also use sensible rate control and consider using the IP Tables rate
control feature for bad connecting clients.

Undoubtably you can get great performance using a quad core a ziggabytes
of memory - but a little sensible optimisation can go a very long way to
keeping cheap hardware very productive.

Hope that helps in some way.

Ron