Re: backupmx with Postfix

From: Nicolas Letellier (no email)
Date: Tue Jul 01 2008 - 06:08:27 EDT

  • Next message: Wietse Venema: "Re: Recipient limit, need advice"

    On Tue, 01 Jul 2008 6:04:41 -0400
    Scott Kitterman <> wrote:

    > On Tue, 1 Jul 2008 11:53:52 +0200 Nicolas Letellier <> wrote:
    > >On Tue, 01 Jul 2008 10:42:02 +0100
    > >Mark Goodge <> wrote:
    > >
    > >>
    > >>
    > >> Nicolas Letellier wrote:
    > >> > On Tue, 01 Jul 2008 11:04:53 +0200
    > >> > mouss <> wrote:
    > >> >> If you have relay_recipient_maps set, then postfix will _reject_, not
    > >> >> bounce. it is the "previous" MTA that generates the bounce. This is why
    > >> >> you should reject on the first server that you manage and let others
    > >> >> bounce or do whatever they want.
    > >> >
    > >> > But, if Postfix rejects a mail, it sends a mail to inform that the mail has been rejected or not?
    > >>
    > >> No. The server that has the mail rejected sends the mail. Consider this
    > >> sequence of events:
    > >>
    > >> 1. User sends mail out via server A.
    > >>
    > >> 2. Server A contacts server B to pass the message on.
    > >>
    > >> 3. Server B accepts the mail.
    > >>
    > >> 4. Server B contacts server C to pass the message on.
    > >>
    > >> 5. Server C rejects the mail.
    > >>
    > >> 6. Server B emails the sender to say that the mail was rejected by C.
    > >>
    > >> You only need to worry about this if you manage server B (as it makes
    > >> you a potential source of backscatter). If you manage server C, then all
    > >> you need to do is reject mail you don't want.
    > >I manage server B (backupmx). Server C is not mine.
    > >The problem is:
    > >
    > >1. User sends mail out via server A to an non existent recipient like 4-ygbG5_yg> >2. Server B checks the recipient and see it does not exists in recipient_maps (so it does not relay it to server C). The mail is rejected.
    > >3. Is server B send an email to User to inform him that his email has not been received (because of a bad recipient) ?
    >
    > No. That's server A's job.
    >
    > Server B rejects the message and never takes responsibility for it. Server A is still responsible for the message and generating the bounce message.
    >
    > Scott K
    Oops.... I made an error in this message... I retry...

    Server A: backup MX (me)
    Server B: smtp.domain.com (true smtp server, managed by another persons who want a backupmx)

    1. User sends mail out via server A to an non existent recipient like 4-ygbG5_yg2. Server A checks the recipient and see it does not exists in recipient_maps (so it does not relay it to server B). The mail is rejected.
    3. Is server A send an email to User to inform him that his email has not been received (because of a bad recipient) ?

    So, Server A (me) will reject the mail and send a bounce... I don't want to bounce mails for it.

    -- 
     -Nicolas.
    

  • Next message: Wietse Venema: "Re: Recipient limit, need advice"





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