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    SMTP redirection

    Scheduled Pinned Locked Moved NAT
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    • A
      almabes
      last edited by

      Just being thorough, you already tried the easy way, right?  In whatever legacy application application specifying smtp.mymailserver.wherever:587 or something along those lines?  Clicking an advanced button or tab and looking for an SMTP port textbox?

      Port forwards are for inbound traffic.  Edit:  Apparently not…I am mistaken, they work both ways.

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      • DerelictD
        Derelict LAYER 8 Netgate
        last edited by

        Traffic subject to port forwarding can be inbound to LAN as easily as it is inbound to WAN.

        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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        • A
          almabes
          last edited by

          @Derelict:

          Traffic subject to port forwarding can be inbound to LAN as easily as it is inbound to WAN.

          I sit on my couch, corrected.  Thanks!

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          • J
            Jakeyg
            last edited by

            Derelict

            legacy mail -> 192.168.0.99
            pfsense -> 192.168.0.1
            external mail server -> for obvious reasons i dont want to give the full ip here.

            Almabes
            yes i have tried with the IP:port_number however after spending an hour with their tech support they say that it will ONLY send to port 25 and that there is no recognition of a :port_number in the address, sadly.  great coding!

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            • A
              almabes
              last edited by

              @Jakeyg:

              yes i have tried with the IP:port_number however after spending an hour with their tech support they say that it will ONLY send to port 25 and that there is no recognition of a :port_number in the address, sadly.  great coding!

              It was worth a mention…Sometimes the easy button gets overlooked.

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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)

                1 Reply Last reply Reply Quote 0
                • 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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