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    Accessing IPsec branch office from an OpenVPN client

    Scheduled Pinned Locked Moved OpenVPN
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    • C
      Cylindric
      last edited by

      Hi, all.

      I have an IPsec VPN between HQ (10.10.0.0) and the Data Centre (172.17.12.0), and I have OpenVPN clients (10.0.9.0) that connect to HQ.

      The problem is that the OpenVPN users cannot currently access servers at the DC. Do I need to add a new Phase 2 config for the 10.0.9.x subnet that the OpenVPN clients are using?

      HQ  <–ipsec--> Data Centre
      /
      |
      OpenVPN
      |
      /
      Home

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      • jimpJ
        jimp Rebel Alliance Developer Netgate
        last edited by

        Yes, you need a Phase 2 on both ends of the IPsec tunnel to cover the 10.0.9.0/24 <-> 172.17.12.0/24 path

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        • DerelictD
          Derelict LAYER 8 Netgate
          last edited by

          And a:

          push "route 10.0.9.0 255.255.255.0"

          In the OpenVPN server config right?

          And firewall rules on the OpenVPN server interface that passes traffic to 10.0.9.0/24…

          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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          • jimpJ
            jimp Rebel Alliance Developer Netgate
            last edited by

            A pushed route would be for 172.17.12.0 - that may or may not be needed, depends on the client settings. If it's already forwarding everything across the VPN that wouldn't be necessary.

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            • DerelictD
              Derelict LAYER 8 Netgate
              last edited by

              Of course I get the networks backwards.  Thanks.

              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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              • C
                Cylindric
                last edited by

                @jimp:

                Yes, you need a Phase 2 on both ends of the IPsec tunnel to cover the 10.0.9.0/24 <-> 172.17.12.0/24 path

                Do I need a 2nd Phase 2 on the HQ end as well? That will be exactly the same as the existing one, as the DC end it all one subnet.

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                • jimpJ
                  jimp Rebel Alliance Developer Netgate
                  last edited by

                  A Phase 2 entry must be defined on both sides of an IPsec tunnel, so yes you'll need that P2 on both the HQ and DC routers

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                  • C
                    Cylindric
                    last edited by

                    But the HQ end is the same for both and I can't create two Phase-two's the same.

                    HQ            DC
                    10.10.0.0/24  172.17.12.0/24
                    10.0.9.0/24

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                    • jimpJ
                      jimp Rebel Alliance Developer Netgate
                      last edited by

                      It's not the same.

                      On the HQ IPsec tunnel you will need:

                      10.10.0.0/24 to 172.17.12.0/24
                      10.0.9.0/24 to 172.17.12.0/24

                      On the DC IPsec tunnel you will need:

                      172.17.12.0/24 to 10.10.0.0/24
                      172.17.12.0/24 to 10.0.9.0/24

                      Each possible path for traffic on IPsec needs to be defined in a Phase 2.

                      Remember: Upvote with the 👍 button for any user/post you find to be helpful, informative, or deserving of recognition!

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                      • C
                        Cylindric
                        last edited by

                        That's what I don't understand though. Here's what I have:

                        HQ End
                        Phase-I: The DC public IP
                        Phase-II: The DC private IP - 172.17.12.0/24 - there is no reference to the internal HQ IP range

                        DC End
                        Phase-I: The HQ public IP
                        Phase-II: The HQ private IP 10.10.0.0/24

                        So following on from what I have, the only place where I see a 10.10.0.0 where I might need to add a 10.0.9.0 is the DC's Phase-II. Everything about a second HQ Phase II would be the same as what's there already.

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                        • jimpJ
                          jimp Rebel Alliance Developer Netgate
                          last edited by

                          You can have multiple Phase 2 entries per Phase 1

                          Just clone the existing P2 entry and change the network to refer to the OpenVPN subnet.

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                          • C
                            Cylindric
                            last edited by

                            Aah, cool I'll try that. I was confused by the "you need a Phase 2 on both ends".

                            I'll try this.

                            I assume I'll have to push the 172.17.12.0/24 route to the OpenVPN clients too.

                            screenshot.PNG
                            screenshot.PNG_thumb

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                            • jimpJ
                              jimp Rebel Alliance Developer Netgate
                              last edited by

                              You do need the Phase 2 defined on both ends though - your screenshot only shows the second P2 on the DC, you also need that on HQ, just change "LAN" to the OpenVPN subnet.

                              And unless you have the OpenVPN client route all traffic across while connected, yes you'll need to push a route.

                              Remember: Upvote with the 👍 button for any user/post you find to be helpful, informative, or deserving of recognition!

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                              Do not Chat/PM for help!

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                              • C
                                Cylindric
                                last edited by

                                It worked! Thank you for your patience! I didn't even think to change the "LAN" part of that config. I was kind of assuming that once you're VPN'd in, you're part of the LAN.

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