This is not a recommendation, will not work for everyone, requires plentiful machine resources, etc. ... disclaimer(n)
Caveats done, FWIW, which may be nothing at all.. .... here is an example of an 'instrumented' R&D server (verbose logging) disposing of a parasite by simply outwaiting it: ======================================================================== 2006-11-03 04:12:52 SMTP connection from [59.117.247.20]:1244 I=[203.194.153.83]:25 (TCP/IP connection count = 1) 2006-11-03 04:13:24 H=59-117-247-20.dynamic.hinet.net [59.117.247.20]:1244 I=[203.194.153.83]:25 Warning: C6 59.117.247.20 59-117-247-20.dynamic.hinet.net Source hostname Blacklisted Hits = 1 Jailed! 32 seconds! 2006-11-03 04:13:56 H=59-117-247-20.dynamic.hinet.net [59.117.247.20]:1244 I=[203.194.153.83]:25 Warning: C7 59.117.247.20 59-117-247-20.dynamic.hinet.net Source Name Brownlisted - Jailed! 32 seconds! 2006-11-03 04:14:28 H=59-117-247-20.dynamic.hinet.net [59.117.247.20]:1244 I=[203.194.153.83]:25 Warning: C8 Sender 59.117.247.20 59-117-247-20.dynamic.hinet.net in dynamic-IP Blacklist Hits = 1 Jailed! 32 seconds! 2006-11-03 04:15:01 H=59-117-247-20.dynamic.hinet.net [59.117.247.20]:1244 I=[203.194.153.83]:25 Warning: C9 59.117.247.20 59-117-247-20.dynamic.hinet.net Blacklisted in (sbl-xbl.spamhaus.org) Hits = 2 Jailed! 32 seconds! 2006-11-03 04:15:01 SMTP connection from 59-117-247-20.dynamic.hinet.net [59.117.247.20]:1244 I=[203.194.153.83]:25 lost ========================================================================== The parasite, which has a valid-but-useless PTR record, BTW, despite being a dynamic-IP adsl service, could have been nailed on any one of, or combination of, of the four faults in acl_smtp_connect alone (C6, C7, C8, C9 are acl clauses), Black and Brown lists are local lookups, and very short lists. This caller never entered the 'full' acl_smtp_helo phase, and our server was never called upon to even give an online acl_smtp_connect rejection message. It gave up and left of its own accord at T+ 2 minutes 9 seconds after arrival. Many will not wait even 64 seconds, and some give up even sooner. No panacea, just one more road to the gulag for the spambots. YMMV, Bill -- ## List details at http://www.exim.org/mailman/listinfo/exim-users ## Exim details at http://www.exim.org/ ## Please use the Wiki with this list - http://www.exim.org/eximwiki/
