1.) What hardware is recommended to run SquirrelMail with Spam Assassin for about 1000 users. We have an old domain and receive about 50,000 to 75,000 emails a day.
That's a pretty medium load. I'll say anything over 1GHz would be more than sufficient. Maybe even a speedy PIII.
2.) How many and which "add on rules" are recommended. If I start adding them one by one, are there some "must have rules" that I should start with first?
Surbl I think. Also, consider greylisting (I use postgrey myself) as that will dramatically reduce the load on Spamassassin.
3.) Any suggestions on how to keep the memory usage down. Sometimes if SA is processing 5 emails at the same time for more than 10 seconds, the memory usages climbs to almost 100%.
That seems odd. Are you running BigEvil?
*** The /etc/procmailrc file:
DROPPRIVS=yes
:0fw: * < 200000 | /usr/bin/spamassassin
:0fw: * ! ^X-Spam-Level:.* * < 200000 | /usr/bin/spamassassin
Why are you running every non-spam through SA twice?
-- sometimes ascii is the best use of bandwidth... Tonya Engst
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