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    SMTP redirection

    Scheduled Pinned Locked Moved NAT
    19 Posts 5 Posters 2.7k Views
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    • DerelictD
      Derelict LAYER 8 Netgate
      last edited by

      Ok, then I'll make one up.  Sheesh.  We'll call it 84.85.86.87

      Firewall > NAT, Create a Port Forward
      Interface: LAN
      Source: *
      Dest: LAN address
      Dest Port: 25
      NAT IP: 84.85.86.87
      NAT Port: 587

      Point your device at 192.168.0.1:25

      Chattanooga, Tennessee, USA
      A comprehensive network diagram is worth 10,000 words and 15 conference calls.
      DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
      Do Not Chat For Help! NO_WAN_EGRESS(TM)

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      • J
        Jakeyg
        last edited by

        Thanks Derelict

        Thats pretty much how i had set it up except that on the legacy server i had it pointing to the email server, with the username and password it said that it registered successfully, however now that i have changed it it also says registered successfully.  however i still dont receive emails.

        grrr legacy crap!

        legacy.jpg
        legacy.jpg_thumb

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        • D
          doktornotor Banned
          last edited by

          Lets try again: The rule should have the legacy crap box IP as source address in the first place, whatever IP that is setup in the "email notification server" and po 25 as destination IP/destination ports, and the real email server and port 587 as NAT IP/NAT ports.

          That's definitely not what's shown on your screenshot, though.

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          • DerelictD
            Derelict LAYER 8 Netgate
            last edited by

            On your crap box the email notification server should be 192.168.0.1

            Does an address need to be present on the interface to do NAT or could he do this?? :

            Firewall > NAT, Create a Port Forward
            Interface: LAN
            Source: 192.168.0.99
            Dest: 84.85.86.87
            Dest Port: 25
            NAT IP: 84.85.86.87
            NAT Port: 587

            Chattanooga, Tennessee, USA
            A comprehensive network diagram is worth 10,000 words and 15 conference calls.
            DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
            Do Not Chat For Help! NO_WAN_EGRESS(TM)

            1 Reply Last reply Reply Quote 0
            • 2
              2chemlud Banned
              last edited by

              There is a good chance this is not going to work anyways. Workaround: Set up a little, LOCAL eMailserver (for Windows: e.g. https://www.hmailserver.com) for the port 25 devices, read eMails from this via a VPN tunnel  with Thunderbird, which  can easily handle such local mail servers.

              Takes you half an hour and your done…

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              • DerelictD
                Derelict LAYER 8 Netgate
                last edited by

                There is a good chance this is not going to work anyways.

                Why not?  It's just a port forward.

                Chattanooga, Tennessee, USA
                A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                Do Not Chat For Help! NO_WAN_EGRESS(TM)

                1 Reply Last reply Reply Quote 0
                • A
                  almabes
                  last edited by

                  I believe you can set the native SMTP on a windows box to do the relay for you, without having to download and install additional server software.

                  Couldn't you just point the PBX at your MX anyway and be done, not try to connect to the client submission port?

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                  • DerelictD
                    Derelict LAYER 8 Netgate
                    last edited by

                    You can also translate only the port on its way through LAN:

                    Firewall > NAT, Create a Port Forward
                    Interface: LAN
                    Source: *
                    Dest: 84.85.86.87
                    Dest Port: 25
                    NAT IP: 84.85.86.87
                    NAT Port: 587

                    Point your device at 84.85.86.87

                    Chattanooga, Tennessee, USA
                    A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                    DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                    Do Not Chat For Help! NO_WAN_EGRESS(TM)

                    1 Reply Last reply Reply Quote 0
                    • 2
                      2chemlud Banned
                      last edited by

                      @Derelict:

                      There is a good chance this is not going to work anyways.

                      Why not?  It's just a port forward.

                      I don't understand much of the SMTP protocol but I could frequently not make the old stuff work with current SMTP servers for sending status eMails. That's why I set up a local server just for receiving these mails. Works fine and better than sending my status eMails as post cards via the the internet… ;-)

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                      • DerelictD
                        Derelict LAYER 8 Netgate
                        last edited by

                        Security is another issue entirely.

                        OP wanted to know how to translate connections to a mail server on 25 to 587.

                        The port forward does that.

                        Chattanooga, Tennessee, USA
                        A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                        DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                        Do Not Chat For Help! NO_WAN_EGRESS(TM)

                        1 Reply Last reply Reply Quote 0
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