On Fri, 2008-08-01 at 08:18 +0200, [EMAIL PROTECTED] wrote: > Hallo postfix-users, > > Occasionally external systems are tying to send mail with a > faked sender address via my system. So far no harm is done, > ad they have not been able to create a real user name. But > I would like to stop them before they use my mail system, > as soon as they make contact. How can I do this? > Example: > Jul 31 15:31:02 duinheks postfix/smtpd[29511]: NOQUEUE: reject: RCPT from > unknown[218.20.152.23]: 550 5.1.0 <[EMAIL PROTECTED]>: Sender address > rejected: > User unknown in local recipient table; from=<[EMAIL PROTECTED]> > to=<[EMAIL PROTECTED]> proto=ESMTP helo=<chenzao>
I dont see any reason for you to worry. You are doing a reject_unauth_destination already There is no way to stop *all* unauthorized connections ( as soon as they connect ? ). You could use RBL's like zen.spamhaus etc on connect that will stop a lot of them but not all
