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    OpenVPN NAT to IPsec

    Scheduled Pinned Locked Moved NAT
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    • D
      denndsd
      last edited by

      Hi,

      current setup:

      Site A: 10.1.0.0/24
      Site B: 192.168.123.0/24
      Site C: 172.16.0.0/24

      All sites are connected by using the following topology.

      Site A > OpenVPN > Site B > IPsec > Site C

      Now there is one obstacle left.
      We have a printer on Site A that needs to be connected from Site C
      We need to NAT all Connections are coming from Site A to Site C by using for example 10.123.2.105/32
      The same for connections coming from Site C to Site A

      The Firewall on Site B should be NAT these connections.

      Site B should connect to Site C by using the netmap address 10.123.1.0/24

      On the IPsec phase 2 there are all SAs are defined for natting as local networks.

      How can i do that ?
      On the internet i couldn't find any informations about it.

      Thanks

      V 1 Reply Last reply Reply Quote 0
      • V
        viragomann @denndsd
        last edited by

        @denndsd
        Not clear, what you want to achieve here.

        Why NAT? Why don't you just route the traffic?

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        • D
          denndsd @viragomann
          last edited by

          @viragomann

          thanks for your reply.
          Unfortuanetly thats not possible from the server provider.
          So we need to NAT the traffic.

          Where i can NAT the traffic coming from site A to Site C ?
          That is needed on Site B
          But what need i to configure ?

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          • V
            viragomann @denndsd
            last edited by

            @denndsd said in OpenVPN NAT to IPsec:

            Where i can NAT the traffic coming from site A to Site C ?

            Best to do this at site B in the IPSec phase 2. Add an additional p2 with these network settings:
            local: network > 10.1.0.0/24
            BINAT: address > 10.123.2.105
            remote: network > 172.16.0.0/24

            However, you need a p2 at C with the remote network 10.123.2.105/32 then.

            How want you nat C to A?

            D 1 Reply Last reply Reply Quote 0
            • D
              denndsd @viragomann
              last edited by

              @viragomann

              yes that was also my idea to nat these at the ipsec.
              I think i need the same to the other direction.

              Do i also need additional firewall rules on the site b ?

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              • D
                denndsd
                last edited by

                I ve tried that.
                Unfortunately that should not worked.
                IP address 10.1.0.100 on site A should be reachable from site C

                Ive set the selected settings on the ipsec vpns
                The site A is connected by openvpn to site b.
                So is it needed to make some changes on the openvpn tunnel on firewall site b ?

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                • V
                  viragomann @denndsd
                  last edited by

                  @denndsd
                  At site A you have to route the site C network 172.16.0.0/24 to site B of course, by adding it to the "remote network" in the OpenVPN settings.
                  At B you need a firewall rule on the VPN interface to pass the traffic.

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                  • D
                    denndsd @viragomann
                    last edited by

                    @viragomann

                    Okay, it doesnt work.

                    My setup.

                    Firewall Site A: Openvpn remote net to 192.168.123.0/24 and 172.16.0.0/24
                    Firewall Site B: Openvpn local network 192.168.123.0/24 172.16.0.0/24
                    On the virtual IPs Ive added every NAT IP Address as /32 for example 10.123.1.23/32
                    The rules are from Site A 10.1.0.0/24 -> Site B 192.168.123.0/24 *
                    Site A 10.1.0.0/24 -> Site C 172.16.0.0/24 *
                    The Firewall Site B: have defined a Outgoing NAT for connections coming from 172.16.0.0/24 to 10.1.0.23 by using a NAT with the NAT IP 10.123.1.23
                    And a port forwarding in the other direction.
                    Thats an example setup for one site with one ip. But is that connect ?
                    I cant reach the site a from site c with this setup.

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