Loading ...
Sorry, an error occurred while loading the content.

Limit the number of messages sent per connection?

Expand Messages
  • Patrick Ben Koetter
    The Yahoo! guidelines for establishing SMTP connections to Yahoo! Mail require a maximum of 5 messages per SMTP connection: Are there any guidelines for
    Message 1 of 6 , Mar 2, 2008
    • 0 Attachment
      The Yahoo! guidelines for establishing SMTP connections to Yahoo! Mail require
      a maximum of 5 messages per SMTP connection:

      "Are there any guidelines for establishing SMTP connections to Yahoo! Mail?"
      <http://help.yahoo.com/l/us/yahoo/mail/postmaster/postmaster-277515.html>

      I know I can use a special default_destination_concurrency_limit to limit the
      number of parallel connections (which is not what I need) and $max_use works
      on incomming connections, but not on outgoing as it seems.

      Is there any parameter to control the maximum number of messages per SMTP
      connection?

      p@rick

      --
      The Book of Postfix
      <http://www.postfix-book.com>
      saslfinger (debugging SMTP AUTH):
      <http://postfix.state-of-mind.de/patrick.koetter/saslfinger/>
    • S P Arif Sahari Wibowo
      ... Hmmm... I thought postfix only send 1 message per SMTP connection. -- (stephan paul) Arif Sahari Wibowo _____ _____ _____ _____ /____ /____/ /____/
      Message 2 of 6 , Mar 2, 2008
      • 0 Attachment
        On Sun, 2 Mar 2008, Patrick Ben Koetter wrote:
        > Is there any parameter to control the maximum number of
        > messages per SMTP connection?

        Hmmm... I thought postfix only send 1 message per SMTP
        connection.

        --
        (stephan paul) Arif Sahari Wibowo
        _____ _____ _____ _____
        /____ /____/ /____/ /____
        _____/ / / / _____/ http://www.arifsaha.com/

        Xinnian Kuaile! 新年快樂 Gongxi Facai 恭喜發財
      • Ralf Hildebrandt
        ... Only in a distan, long gone past: http://www.postfix.org/CONNECTION_CACHE_README.html -- Ralf Hildebrandt (Ralf.Hildebrandt@charite.de)
        Message 3 of 6 , Mar 2, 2008
        • 0 Attachment
          * S P Arif Sahari Wibowo <lists@...>:

          >> Is there any parameter to control the maximum number of messages per
          >> SMTP connection?
          >
          > Hmmm... I thought postfix only send 1 message per SMTP connection.

          Only in a distan, long gone past:
          http://www.postfix.org/CONNECTION_CACHE_README.html

          --
          Ralf Hildebrandt (Ralf.Hildebrandt@...) snickebo@...
          Postfix - Einrichtung, Betrieb und Wartung Tel. +49 (0)30-450 570-155
          http://www.arschkrebs.de
          Fat lady: I was Rubenesque before I was fat. --Metropolitan Museum of Art
        • S P Arif Sahari Wibowo
          ... Ah, that may explain all those emails to yahoo which ended up deferred. :-) So as the OP question, is there any way to limit this feature based on the
          Message 4 of 6 , Mar 2, 2008
          • 0 Attachment
            On Sun, 2 Mar 2008, Ralf Hildebrandt wrote:
            > http://www.postfix.org/CONNECTION_CACHE_README.html

            Ah, that may explain all those emails to yahoo which ended up
            deferred. :-) So as the OP question, is there any way to limit
            this feature based on the number of message per connection, or
            turn off this feature entirely based on domain?

            --
            (stephan paul) Arif Sahari Wibowo
            _____ _____ _____ _____
            /____ /____/ /____/ /____
            _____/ / / / _____/ http://www.arifsaha.com/

            Xinnian Kuaile! 新年快樂 Gongxi Facai 恭喜發財
          • Noel Jones
            ... Postfix smtp connection caching is time based (how long can a connection stay active), not count based, so there is no control to limit the number of
            Message 5 of 6 , Mar 2, 2008
            • 0 Attachment
              Patrick Ben Koetter wrote:
              > The Yahoo! guidelines for establishing SMTP connections to Yahoo! Mail require
              > a maximum of 5 messages per SMTP connection:
              >
              > "Are there any guidelines for establishing SMTP connections to Yahoo! Mail?"
              > <http://help.yahoo.com/l/us/yahoo/mail/postmaster/postmaster-277515.html>
              >
              > I know I can use a special default_destination_concurrency_limit to limit the
              > number of parallel connections (which is not what I need) and $max_use works
              > on incomming connections, but not on outgoing as it seems.
              >
              > Is there any parameter to control the maximum number of messages per SMTP
              > connection?
              >
              > p@rick
              >

              Postfix smtp connection caching is time based (how long can a
              connection stay active), not count based, so there is no
              control to limit the number of messages per connection to some
              arbitrary number.

              http://www.postfix.org/postconf.5.html#smtp_connection_cache_on_demand
              http://www.postfix.org/postconf.5.html#smtp_connection_cache_time_limit

              You can turn off connection caching for a specific transport
              in master.cf.

              abbreviated example:
              # transport
              yahoo.com nocache:

              # master.cf
              nocache unix - - n - - smtp
              -o smtp_connection_cache_on_demand=no

              --
              Noel Jones
            • Noel Jones
              ... After studying yahoo s instructions, it seems they don t intend to penalize you for attempting more than 5 messages per connection, they just disconnect
              Message 6 of 6 , Mar 2, 2008
              • 0 Attachment
                Noel Jones wrote:
                > Patrick Ben Koetter wrote:
                >> The Yahoo! guidelines for establishing SMTP connections to Yahoo! Mail
                >> require
                >> a maximum of 5 messages per SMTP connection:
                >>
                >> "Are there any guidelines for establishing SMTP connections to
                >> Yahoo! Mail?"
                >>
                >> <http://help.yahoo.com/l/us/yahoo/mail/postmaster/postmaster-277515.html>
                >>
                >> I know I can use a special default_destination_concurrency_limit to
                >> limit the
                >> number of parallel connections (which is not what I need) and $max_use
                >> works
                >> on incomming connections, but not on outgoing as it seems.
                >>
                >> Is there any parameter to control the maximum number of messages per SMTP
                >> connection?
                >>
                >> p@rick
                >>
                >
                > Postfix smtp connection caching is time based (how long can a connection
                > stay active), not count based, so there is no control to limit the
                > number of messages per connection to some arbitrary number.
                >
                > http://www.postfix.org/postconf.5.html#smtp_connection_cache_on_demand
                > http://www.postfix.org/postconf.5.html#smtp_connection_cache_time_limit
                >
                > You can turn off connection caching for a specific transport in master.cf.
                >
                > abbreviated example:
                > # transport
                > yahoo.com nocache:
                >
                > # master.cf
                > nocache unix - - n - - smtp
                > -o smtp_connection_cache_on_demand=no
                >

                After studying yahoo's instructions, it seems they don't
                intend to penalize you for attempting more than 5 messages per
                connection, they just disconnect after the 5th and force you
                to make a new connection if you have more to say. They say in
                bold print:
                "Reestablish connections if you do not get an error code"

                If that's really what they are doing, Postfix should deal with
                it gracefully with no changes or special config.

                --
                Noel Jones
              Your message has been successfully submitted and would be delivered to recipients shortly.