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    Port forward to other site over OpenVPN Client

    Scheduled Pinned Locked Moved OpenVPN
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    • J
      johntjampens
      last edited by

      Hi Guys,

      I'm struggling with correctly setting up a port forward from site A to a server in site B.

      Some info about my config:
      Site A :
      WAN : 4 public IP's & 1 PPPoE
      A.A.A.A, B.B.B.B, C.C.C.C and D.D.D.D
      Open VPN Server
      Set up of portforward from C.C.C.C to local ip (site B) : 192.168.10.22
      Tunnel network : 192.168.123.1

      Site B :
      WAN : 1 PPPoE dynamic IP
      OpenVPN Client
      Tunnel network : 192.168.123.2
      Local subnet : 192.168.10.0/24

      I need a port forward from site A (C.C.C.C) to site B on IP 192.168.10.22 on port 25.

      The server in site B already has a working connection over the VPN, and is already showing as wan ip the address C.C.C.C.
      From site A to B telnet on port 25 no problem.
      From Any to C.C.C.C:25 is not working, no connection.

      So i has to do something with the the port translation, can someone help me in the right direction?

      With kind regards,

      John

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      • DerelictD
        Derelict LAYER 8 Netgate
        last edited by Derelict

        On site B you have to:

        1. Assign an interface to the OpenVPN instance
        2. Ensure the traffic passing the incoming connections to the server does not match the firewall rules on the OpenVPN tab and does match the rules on the assigned interface tab.

        In this situation it just makes sense to disable/delete the rules on the OpenVPN tab and put them on the assigned interface tab unless you have multiple OpenVPN instances on that site.

        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)

        J 1 Reply Last reply Reply Quote 0
        • J
          johntjampens @Derelict
          last edited by

          @derelict Thanks for the quick response.
          I already have on site B an interface for the OpenVPN.
          It's not quite clear what you mean about your second sentence. (Not matching of the traffic, because there is already an OpenVPN instance for connecting to site A from anywhere for the mobile clients.

          With kind regards,

          John

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          • DerelictD
            Derelict LAYER 8 Netgate
            last edited by

            Right. When the incoming traffic matches that you do not get the benefit of reply-to which will direct replies from the server back out OpenVPN instead of according to the routing table.

            So the traffic being port forwarded over the tunnel cannot match those pass rules. It has to be matched by rules on the assigned interface tab instead.

            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)

            J 1 Reply Last reply Reply Quote 0
            • J
              johntjampens @Derelict
              last edited by johntjampens

              @derelict said in Port forward to other site over OpenVPN Client:

              Right. When the incoming traffic matches that you do not get the benefit of reply-to which will direct replies from the server back out OpenVPN instead of according to the routing table.
              So the traffic being port forwarded over the tunnel cannot match those pass rules. It has to be matched by rules on the assigned interface tab instead.

              Trying to analyse you response.
              You mean the matching rules in site B?
              In site A i don't have an interface for that, only on the OpenVPN client.

              With kind regards,

              John

              1 Reply Last reply Reply Quote 0
              • DerelictD
                Derelict LAYER 8 Netgate
                last edited by

                Please post the rules on Site B's OpenVPN tab and the assigned interface tab. And please include the private IP address and port of the server at that site that is being forwarded to.

                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)

                J 1 Reply Last reply Reply Quote 0
                • J
                  johntjampens @Derelict
                  last edited by

                  @derelict said in Port forward to other site over OpenVPN Client:

                  And please include the private IP address and port of the server at that site that is being

                  Hi,

                  MILIN INTERFACE

                  Firewall Rules MILIN (site to site VPN)

                  	States 		Protocol 	Source 	Port 	Destination 	Port 	Gateway 	Queue 	Schedule 	Description 	Actions
                  	1 /52 KiB	IPv4 TCP 	* 		* 		* 				* 		* 			none 	  		
                  

                  Firewall Rules OpenVPN (Mobile VPN)
                  Currently empty (for testing with my site to site vpn, no production at the moment)

                  Port forwarding:

                  Firewall NATPort Forward

                  		Interface 	Protocol 	Source Address 	Source Ports 	Dest. Address 	Dest. Ports 	NAT IP 	NAT Ports 	Description 	Actions
                  		WAN 	TCP 	* 	* 	C.C.C.C 	443 (HTTPS) 	192.168.10.22 	443 (HTTPS) 	Toegang tot Mailserver Digiplay 	
                  		WAN 	TCP 	* 	* 	C.C.C.C  	80 (HTTP) 	192.168.10.25 	80 (HTTP) 		
                  		WAN 	TCP 	* 	* 	C.C.C.C  	25 (SMTP) 	192.168.10.22 	25 (SMTP) 	Mailserver Digiplay
                  
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                  • DerelictD
                    Derelict LAYER 8 Netgate
                    last edited by

                    How about screen shots including the tabs. Hard to make sense of that. Reference site A or site B based on your prior description.

                    It's looking more like a firewall on the server but based on that it's hard to tell.

                    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)

                    J 1 Reply Last reply Reply Quote 0
                    • J
                      johntjampens @Derelict
                      last edited by

                      @derelict I got it working.
                      Idd the Interface needed to have the traffic defined on which the gateway was defined.

                      Thx for the response.

                      1 Reply Last reply Reply Quote 0
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