Jeff, On 17.07.2005 23:10, Jeff Buehler wrote: > Thanks, Sönke - > > I was hoping to keep them in the queue for awhile, but I am collecting > 500 or more undeliverables a day presently since I am forwarding to a > domain that is getting heavily spammed. > > When spammers send spam to bogus users at the busy Exchange server I am > forwarding to, it predicatably sends back the "user doesn't exist" > message, then xmail correctly attempts to send that back to the spammer > who, of course, doesn't accept incoming mail, and so the message is > undelivered. > > Are you aeware of a better way to handle this sort of interaction? I > could create a user to match every user on the Exchange server and at > least cut out a hop, but XMail will still then try to send the "no user > by that name" reply back to the spammer. I guess it's important to > notify valid senders to the domain that a given user doesn't exist, > though... Is that an RFC requirement?
My solution is to setup a cmdaliases file for each user that is being forwarded. So your mail server does not send bogus bounce mails into the internet. It's quite simple because XMail then sends directly "550 user not found" in the SMTP session. So there is _NO_ bounce mail generated and your Exchange server gets only these messages that it can handle. And if there is a non-spam sender that types a wrong mail adress he'll get a bounce message from the server that tries to send to yours. I hope you got the advantage of that way. And note: Some providers are blacklisting servers with high bounce volumes. So someone - aware or unaware - could exploit your mailserver with wrong sender addresses and wrong rcpt addresses. now your mailserver weirdly sends out bounces back to the faked sender mailserver and could get blacklisted. So it's always a good idea to use forwarding for each user and not for whole domains. That differs the lame admins from the good ones *SCNR* - To unsubscribe from this list: send the line "unsubscribe xmail" in the body of a message to [EMAIL PROTECTED] For general help: send the line "help" in the body of a message to [EMAIL PROTECTED]
