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    IPsec Site-to-Site with NAT

    Scheduled Pinned Locked Moved IPsec
    28 Posts 3 Posters 2.5k Views
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    • J
      jf5264835
      last edited by

      Screen Shot 2019-08-25 at 1.03.38 PM.png

      They are just setup as Virtual IPs on the WAN interface. Browsing to one that hasn't been setup yet with 1:1 nat takes you to the pfSense login page (https://54.39.70.254/), and those addresses reply to ICMP requests, so I know that part is good.

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      • DerelictD
        Derelict LAYER 8 Netgate
        last edited by Derelict

        Well whatever is set up on WAN has nothing to do with the IPsec NAT.

        That configures what happens to the NAT in the tunnel itself.

        When the other side connects to 172.21.69.1 what do you want to happen?

        Specifically, what connecting to what is not working?

        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
          jf5264835
          last edited by

          I want to be able to connect to say, 54.39.70.254 in a web browser, and have it show content from 172.21.0.11. From my understanding, I'd need source NAT for the incoming traffic, and a 1:1 NAT for traffic for External IP>Internal Host IP.

          DerelictD 1 Reply Last reply Reply Quote 0
          • DerelictD
            Derelict LAYER 8 Netgate @jf5264835
            last edited by

            @jf5264835

            jf5264835 less than a minute ago

            I want to be able to connect to say, 54.39.70.254 in a web browser,

            Connect to that from where?

            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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            • DerelictD
              Derelict LAYER 8 Netgate
              last edited by

              If you are talking about connections coming into WAN then out over the IPsec to a server across the tunnel then that is not the correct method.

              You would need to set the source on the phase 2 to Network 0.0.0.0/0 with a NAT to Address 54.39.14.0 to make that traffic interesting to IPsec. The WAN external 1:1 address in that case would be 54.39.70.254, not 54.39.70.0.

              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
                jf5264835
                last edited by

                Anywhere. Public IP address, so basically anywhere,anytime.

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                • DerelictD
                  Derelict LAYER 8 Netgate
                  last edited by

                  When a connection attempt comes into WAN, the 1:1 NAT translates the destination address. When the connection goes out the IPsec tunnel the NAT there translates the source address.

                  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
                    jf5264835
                    last edited by

                    Screen Shot 2019-08-25 at 1.23.29 PM.png

                    So I'd want the P2 to be like this?

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                    • DerelictD
                      Derelict LAYER 8 Netgate
                      last edited by

                      It has to be to have a hope of the traffic being put into IPsec at all.

                      OpenVPN is much more flexible in this regard, but IPsec might be able to be coerced to work.

                      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
                        jf5264835
                        last edited by

                        Screen Shot 2019-08-25 at 1.57.13 PM.png

                        ICMP comes in and gets NATed, but nothing goes through the IPsec tunnel.
                        Screen Shot 2019-08-25 at 1.59.35 PM.png

                        Time to try OpenVPN?

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                        • DerelictD
                          Derelict LAYER 8 Netgate
                          last edited by

                          That does not look like the traffic is being picked up by the traffic selectors after the NAT happens. It looks like it is just going back out the WAN.

                          I was expecting you to be pinging .254 from the outside, not .0

                          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
                            jf5264835
                            last edited by

                            I was using the .254 as an example, been primarily trying things with just the .0.

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

                              What is the output of swanctl --list-sas ??

                              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
                                jf5264835
                                last edited by

                                con1000: #156, ESTABLISHED, IKEv1, 07efff97c8376e52_i* 1270ead44af08916_r
                                  local  '167.114.185.196' @ 167.114.185.196[4500]
                                  remote '76.31.172.16' @ 76.31.172.16[4500]
                                  AES_CBC-128/HMAC_SHA1_96/PRF_HMAC_SHA1/MODP_2048
                                  established 38s ago, reauth in 27959s
                                  con1000: #70, reqid 6, INSTALLED, TUNNEL-in-UDP, ESP:AES_CBC-128/HMAC_SHA1_96/MODP_2048
                                    installed 38s ago, rekeying in 2759s, expires in 3562s
                                    in  c91e225c,      0 bytes,     0 packets,    38s ago
                                    out ca6a137a,      0 bytes,     0 packets
                                    local  54.39.14.0/32|/0
                                    remote 172.21.0.0/24|/0
                                
                                1 Reply Last reply Reply Quote 0
                                • J
                                  jf5264835
                                  last edited by

                                  Well, doesn't matter now, I got it properly working using OpenVPN, took all of an hour including coffee time, vs IPsec which has been weeks in the making. Thank you for steering me into the light @Derelict

                                  1 Reply Last reply Reply Quote 1
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