• Instant Messaging Server

FAQs and Info.Using SORBS with iPlanet Messaging Server 5.xdetails the 2 ways of stopping spam with the SORBS DNS block list. The first (and the recomended way) is toadd a mapping table rule such as:PORTACCESS. $C$ INTERNALIP;$3 $Y$ETCP. 25.$C$ /bin/msg/imta/lib/dnsverify.so,dnsverifydomainport,$1,dnsbl.sorbs.net.EXTERNAL$EORIGMAILACCESSTCP. 25.

Instant Messaging Server

SMTP. tcplocal.@.$C$ /bin/msg/imta/lib/dnsverify.so,dnsverifydomain,$1,dnsbl.sorbs.net.$EThis will block connections on receiving a 'RCPT TO:' request. Alternatively you can configure thedispatcher (using dispatcher.cnf) as follows:SERVICE=SMTPPORT=25!rest of normal options.DNSVERIFYDOMAIN=spam.dnsbl.sorbs.netDNSVERIFYDOMAIN=http.dnsbl.sorbs.net!etc.The latter case, the incoming connection will be rejected at the banner.This is how the SORBS SMTP proxy server works by default.

It's disadvantageis some clients (incoming connections from servers are considered clients to)ignore the 554 banner as a PERMANENT fail and keep trying to resent until themessage times out.