root@smtpin0:/ # postconf -n |grep postscreen
postscreen_blacklist_action = drop
postscreen_cache_map = proxy:btree:/var/db/postfix/postscreen_cache
postscreen_dnsbl_action = enforce
postscreen_dnsbl_sites = bl.spamcop.net*1 b.barracudacentral.org*1 cbl.abuseat.org=127.0.0.2*3 b.barracudacentral.org=127.0.0.2*3 bl.spamcop.net=127.0.0.2*2 hostkarma.junkemailfilter.com=127.0.0.2*2 hostkarma.junkemailfilter.com=127.0.0.4*1 bl.spameatingmonkey.net=127.0.0.2*2 backscatter.spameatingmonkey.net=127.0.0.1*1 psbl.surriel.com=127.0.0.2*7 bl.nosolicitado.org*3 hostkarma.junkemailfilter.com=127.0.0.[1;5]*-5 ips.whitelisted.org=127.0.0.2*-3 list.dnswl.org=127.[0..255].[0..255].0*-2 list.dnswl.org=127.[0..255].[0..255].1*-3 list.dnswl.org=127.[0..255].[0..255].[2..255]*-4
postscreen_greet_action = drop
postscreen_greet_banner = $smtpd_banner
postscreen_greet_wait = 6
postscreen_reject_footer = Sorry, can't help you.