On Thu, Mar 18, 2010 at 4:53 PM, Kaleb Hosie <kho...@spectraaluminum.com> wrote: > Maybe this is not the best practice, however I don't block any incoming mail > (destined for a legit address) for the same reason. I use a program called > SpamAssassin Quarantine and I let it scan for the spam. >
content scanning every message is not practical for sites with a large volume of mail. even if you have the resources to do this, users tend to ignore the quarantine reports, and since senders are not notified that their message has been not been received, you get mails that "just go missing". better in many cases to let the sender know (via an SMTP rejection, *not* any sort of NDR). nothing is perfect, it's a judgment call based on what your users expect and what hardware you have available to try and provide it. > Spam is put in quarantine and doesn't effect the users. It sends out an email > every day letting the user release the mail. > > Hope that helps > > > -----Original Message----- > From: owner-postfix-us...@postfix.org > [mailto:owner-postfix-us...@postfix.org] On Behalf Of Kay > Sent: Thursday, March 18, 2010 2:43 PM > To: postfix-users@postfix.org > Subject: Mail rejected on "Received From" > > Hi guys, > > I often see mail being rejected by recipient servers because an IP in a > Received From header is blacklisted somewhere. > > This strikes me as a rather bad practise, since it undermines the whole idea > of SMTP authentication. > > Here's an example reject: > > 550 5.7.1 This system has been configured to reject your mail. An IP address > (xx.xx.xx.xx) found in the message's 'Received:' headers is listed by the > lookup site 'sbl-xbl.spamhaus.org.'. > > xx.xx.xx.xx is the client's IP, a regular dynamic IP on a broadband > connection. Which shouldn't have any relevance. > > To make matters worse, the offending recipient site does not accept mail for > abuse/postmaster or any of the usual aliases. > > How do you engage hosts like these to resolve such issues? > > Thanks > K >
