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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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    • 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)

      1 Reply Last reply Reply Quote 0
      • J
        jf5264835
        last edited by

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

        1 Reply Last reply Reply Quote 0
        • 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.

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                    • 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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