[CentOS] Planning Mail Server (with low resources)

Tue Dec 6 13:56:42 UTC 2005
Scot L. Harris <webid at cfl.rr.com>

On Mon, 2005-12-05 at 23:16, Rodrigo Barbosa wrote:
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> On Tue, Dec 06, 2005 at 03:56:50AM +0000, Karanbir Singh wrote:
> > >First off, dump either antivirus or antispam on that machine. You
> > >don't have enough memory to keep both happy.
> > 
> > How about using MailScanner ? and wrap that around clamav + 
> > spamassassin, you can run it with 2 - 4 threads on a machine with 
> > 256megs of ram, and since spamassassin runs via its perl interface 
> > locally ( and not via spamd ), it uses up no resources while its not 
> > running.
> 
> Yeah, that will work for a month or 2. After than, the bayesian database
> will start to get huge, and spamassassin will take a lot of time to
> start and use a lot of memory.

So implement greylisting.  Had one server that was getting swamped
during particularly heavy spam storms.  Setup greylisting and the box
has not broken a sweat since.

You should be able to find greylisting options for most MTAs.  I used
milter-greylist with sendmail.  Still kept spamassassin in the mix, it
caught the few spam that got past greylisting.

Went from about 8000 spam a day down to 8 or 10 spam a day after
implementing greylisting.