Postfix - Remove sender from forward / receiver list

  • Hey there,
    is it possible to remove sender from forward / receiver list? Small example:

    I have following mail accounts:
    list@example.tld -> Redirection to user1@example.tld; user2@example.tld; user3@example.tld; user4@example.tld

    user1@example.tld sends a mail to list@example.tld. user1@example.tld and the other 3 users receive the mail.

    Want to have:
    user1@example.tld sends a mail to list@example.tld. Only the other 3 users receive the mail.

    PS: This should be done automatically, don't want to map... :-)

  • Hi Ninos,
    I think I have the same issue, with a slightly different use case.

    Assuming example.tld is a domain hosted within i-MSCP:

    One of my users has an e-mail forwarder:
    This forwards on to an another account:
    Note that in my use case, it doesn't matter if "any-domain.tld" is another within my server, or an external account like gmail, etc.

    The e-mail is delivered as expected:

    1. my-own-account@my-domain.tld ---sends-to-> my-user@example.tld ---forwarded-> my-user-another-account@any-domain.tld

    If I send an e-mail to my-user@example.tld, it correctly forwards to my-user-another-account@any-domain.tld
    When my-user-another-account@any-domain.tld replies to my e-mail (using the standard Reply mechanism not Reply All), it comes from my-user-another-account@any-domain.tld - this is expected of course.

    1. my-user-another-account@any-domain.tld ---sends-to-> my-own-account@my-domain.tld

    The problem arises when there is more than one recipient:

    I send an e-mail to my-user@example.tld and some-other-user@any-domain.tld
    Again, any-domain.tld can literally be any domain, it doesn't matter if it is the same domain as the sender, or if it is hosted within my server. some-other-user@any-domain.tld is just "any e-mail address".

    1. my-own-account@my-domain.tld ---sends-to-> my-user@example.tld ---forwarded-> my-user-another-account@any-domain.tld some-other-user@any-domain.tld

    That all works correctly, as expected.

    However, when the recipient who has the forwarder uses Reply All, their e-mail client looks at the headers, etc. and says:

    Quote from my-user-another-account@any-domain.tld e-mail client

    Wait! This was sent to "my-user@example.tld" and "some-other-user@any-domain.tld" - neither of those are me! I'm "my-user-another-account@any-domain.tld" - I will add "my-user-another-account@any-domain.tld" as the From address and move "my-user@example.tld" to the list of CC addresses.

    The e-mail is then sent by the user, and because their own forwarder is on the CC list, they receive a copy of their own e-mail too:

    1. my-user-another-account@any-domain.tld ---sends-to-> my-own-account@my-domain.tld some-other-user@any-domain.tld my-user@example.tld ---forwarded-> my-user-another-account@any-domain.tld

    Next, some-other-user@any-domain.tld replies to this e-mail:

    1. some-other-user@any-domain.tld ---sends-to->
    2. my-own-account@my-domain.tld
    3. my-user-another-account@any-domain.tld
    4. my-user@example.tld ---forwarded-> my-user-another-account@any-domain.tld

    So from that point on, the person with the forwarder gets two copies of every e-mail which in which recipients use Reply All.

    Of course, nothing is actually going wrong, per se. The e-mail system is working exactly as it's technically supposed to - but it is annoying and discourages users from using the very useful forwarders.

    Does this sound like we're having the same problem from different angles?

  • Hey there, it's not the same problem but with the same result hehe. I'm sure the Mailman plugin, which will be released soon, will solve our problems :)

  • Ahh, I see :-) Yes this all came about as a result of not having access to Mailman too :-)

    I'm looking forward to the release of the new plugin (as I imagine you are too!)