Re: Exim & spamd.. eating all my memory and cpu

On Fri, 4 Jun 2004, j.linn wrote:

| Another approach is to cut down the number of connects that EXIM permits
| to meet the capacity of your system. My current setting for a mailhub
| model which routes email to other mailservers, are
|
| smtp_accept_max = 100
| smtp_accept_queue = 75
| smtp_accept_reserve = 50
| smtp_reserve_hosts = 139.133.0.0/16		[local network]
| smtp_connect_backlog = 20
| smtp_load_reserve = 3

Yup - these settings are well worth tuning.

We also set:

  smtp_accept_max_per_host = 5

which is very effective at curtailing the ability of any single "flooder"
host to DoS our SpamAssassin boxes.

I concur with other suggestions in this thread:

- only scan incoming mail (for spam - scan ALL mail for viruses, if you
   have windoze boxes around ! )

- don't bother scanning big messages for spam

Another point is to try and reject as much as possible before cranking up
SA.  The RCPT acl is a good place to perform DNSrbl checks, tests for
preposterous HELOs and so on.  In our environment, these tests get rid of
so much junk that SA hardly runs at all....

( relatively speaking )

--
Chris Edwards, Glasgow University Computing Service