In case you missed this post - here is a reasonable recipe based on many
years of senamil server admin'ing - feel free to modify, improve or ignore!
On 06/25/2010 09:26 PM, Genes MailLists wrote:
1) FEATURE(`enhdnsbl', `bl.spamcop.net', `', `t',
`127.0.0.2.')dnl
Add more if you want, but additional RBL's do not add too much.
2) FEATURE(`greet_pause', `3000')dnl
Remove the GreetPause delay for any trusted hosts - not vital >
but
will speed up incoming mail from trusted MX hosts.
e.g.
GreetPause:mail-bw0-f1.google.com 0
3) FEATURE(delay_checks)dnl
FEATURE(`block_bad_helo') dnl
4) FEATURE(`require_rdns') dnl
5) Maintain access list -
- mine contains (large) number of netblocks
- use senderbase to help identify netblocks and get more info
about IP's.
http://www.senderbase.org
- only look at the last Received line hitting your mail server
You may choose what you want to block here - e.g. residential IP's
6) I have also iptable Firewall blocks for undesirables (I use some
country blocks in addition to a list of naughties)
7) run spamassasin (at the back end not the border server if you're
running internal and border sendmails).