Titanus Eramius: > Besides aptget.dk this server also hosts cogky.dk (among others), and > while unknown recipients is being correctly rejected with a 550 when > sent to aptget.dk, they are not when sent to the other virtual domains. > Instead they are accepted and then returned by the MAILER_DAEMON, which > in turn opens the server to backscatter.
Where is cogky.dk defined: mydestination, virtual_alias_domains, virtual_mailbox_domains, relay_domains? It must be only one. This answer determines where the "known" recipients must be listed: local_recipient_maps, virtual_alias_maps,m virtual_mailbox_maps, relay_recipients. If you list the domain or recipients in the wrong place then mail will be rejected. See http://www.postfix.org/ADDRESS_CLASS_README.html Wietse
