Ok thanks for your answer but I have another question: if I reject the e-mail instead of sending the non delivery notification, how can a "good" user be notified of the fact that his e-mail was not delivered? Claudio On 14/02/23 19:48, dovecot at ptld.com wrote:>>> I have an external MTA configured with Postfix that delivers email >>> to an internal IMAP/LMTP >>> Dovecot server configured to bind an LDAP to check if users exist. >> >> You should have postfix do the checking for whether or not users exist >> and then have postfix reject and deny the message.? Then you don't >> care because the IP of the postfix server is almost certainly your MX >> server. > > > Plus backscatter. Sending a fail notification back to the sender (vs > rejecting) puts your mail server at risk of sending spam to email > accounts that had their address forged. And thus maybe yoru server > being added to a spam blacklist.-------------- next part -------------- A non-text attachment was scrubbed... Name: smime.p7s Type: application/pkcs7-signature Size: 3517 bytes Desc: S/MIME Cryptographic Signature URL: <https://dovecot.org/pipermail/dovecot/attachments/20230215/055e25b8/attachment.bin>
On 2023-02-15 6:41 a.m., Claudio Corvino wrote:> Ok thanks for your answer but I have another question: if I reject the > e-mail instead of sending the non delivery notification, how can a > "good" user be notified of the fact that his e-mail was not delivered? > > ClaudioThat should be the job of the sender's MTA, not you.