Erick Calder wrote: > On Sep 27, 2009, at 12:53 AM, LuKreme wrote: > >> On Sep 27, 2009, at 0:53, Erick Calder <e...@arix.com >> <mailto:e...@arix.com>> wrote: >> >>> if the message were for <mailto:no-ex...@arix.com>no-ex...@arix.com >>> <mailto:no-ex...@arix.com> then it gets rerouted to >>> <mailto:n...@arix.com>n...@arix.com <mailto:n...@arix.com> which also >>> doesn't exist and therefor bounces. >> >> Yes, it bounces. This makes you a backacatter source. This is bad. > > but doesn't my postfix server bounce by default when receiving a mail > for an inexistent address? and if it doesn't, how are users who misspell > my address to know their message didn't get delivered?
postfix doesn't bounce when it rejects mail to invalid recipients. it is the sending MTA which generates the bounce. as already suggested, put the user part in the expression, or use sql. I have already posted an example, so I won't repeat it here.
