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    Clients cannot communicate with each other.

    Scheduled Pinned Locked Moved OpenVPN
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    • S
      scilek
      last edited by scilek

      network_setup.png
      pfSense -> 2.4.4 p3

      I am trying to get all clients from all branches to communicate with each other. To this end, I set up two OpenVPN servers on the HQ router:

      VPNS_A:
      Type -> Peer to Peer (Shared Key)
      Port -> 1194
      Tunnel Network -> 10.0.0.0/24
      Remote Networks -> 172.16.1.0/24

      VPNS_B:
      Type -> Peer to Peer (Shared Key)
      Port -> 1195
      Tunnel Network -> 10.0.1.0/24
      Remote Networks -> 172.16.2.0/24

      And below are client configurations:

      BRANCH_A:
      Server-> A.B.C.D:1194
      Tunnel Network -> 10.0.0.0/24
      Remote Networks -> 172.16.0.0/24, 172.16.2.0/24

      BRANCH_B:
      Server-> A.B.C.D:1195
      Tunnel Network -> 10.0.1.0/24
      Remote Networks -> 172.16.0.0/24, 172.16.1.0/24

      I created the necessary firewall rules for all routers and enabled the VPN interfaces. I can ping clients at HQ from both branches but cannot ping a client at BRANCH_A from BRANCH_B or the the other way around. What am I missing here? Do I have to take any further steps to make it happen?

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      • M
        marvosa
        last edited by marvosa

        If the remote networks are configured exactly as you have them listed, there's your issue. Each site is only routing 1 IP over the tunnel instead of the entire network. Modify the "Remote Networks" section at each site to reflect the networks you want to connect to on the remote end:

        VPNS_A:
        Type -> Peer to Peer (Shared Key)
        Port -> 1194
        Tunnel Network -> 10.0.0.0/24
        Remote Networks -> 172.16.1.0/24

        VPNS_B:
        Type -> Peer to Peer (Shared Key)
        Port -> 1195
        Tunnel Network -> 10.0.1.0/24
        Remote Networks -> 172.16.2.0/24

        And below are client configurations:

        BRANCH_A:
        Server-> A.B.C.D:1194
        Tunnel Network -> 10.0.0.0/24
        Remote Networks -> 172.16.0.0/24, 172.16.2.0/24

        BRANCH_B:
        Server-> A.B.C.D:1195
        Tunnel Network -> 10.0.1.0/24
        Remote Networks -> 172.16.0.0/24, 172.16.1.0/24

        Once that's done, bounce both tunnels @ HQ and you should be good to go.

        S 1 Reply Last reply Reply Quote 0
        • S
          scilek @marvosa
          last edited by

          @marvosa

          I have just checked my configurations. There is nothing out of order there. I made the mistake in the post.

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          • Y
            yumcheese
            last edited by

            On the OpenVPN Server settings, under "Tunnel Settings" there is a checkbox for "Inter-client communication" Allow communication between clients connected to this server. You probably need that checked.

            Not sure if you have that particular setting available in your specific mode. I see it on Server Mode: "Remote Access (SSL/TLS + User auth)".

            S 1 Reply Last reply Reply Quote 0
            • S
              scilek @yumcheese
              last edited by scilek

              @yumcheese

              I don't have that under the "Peer to Peer (Shared Key)" option. But I don't believe that is the issue anyway since I can ping any client at HQ from any other branch and vice versa. The problem is that I cannot ping clients that reside on another branch.

              HQ -> ping 172.16.1.2 -> OK
              HQ -> ping 172.16.2.2 -> OK
              BRANCH_A -> ping 172.16.0.2 -> OK
              BRANCH_B -> ping 172.16.0.2 -> OK
              BRANCH_A -> ping 172.16.2.2 -> FAIL!
              BRANCH_B -> ping 172.16.1.2 -> FAIL!

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              • T
                tman904
                last edited by

                If the vpns connect back and talk through hq assuming it's a hub/spoke, make sure the hq will route that traffic between the spokes.

                S Y 2 Replies Last reply Reply Quote 0
                • S
                  scilek @tman904
                  last edited by

                  @tman904

                  That was my guess, but I think OpenVPN takes cares of that. What if I am wrong? How do I make the HQ router route traffic between the spokes? (Forgive my ignorance, oh high gurus of networking!)

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                  • Y
                    yumcheese @tman904
                    last edited by yumcheese

                    @tman904
                    Yes, that sounds like the problem. Also, is VPNS_B needed? I believe you should be able to just have the branch offices connect to VPNS_A. That might make the path of travel easier. Do you see a route to the other Branch office IP/Tunnel when you look at Diagnostics | Routes on the branch offices?

                    Maybe you need to use the "Client Specific Overrides" feature to pass the routing info.

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                    • S
                      scilek @yumcheese
                      last edited by

                      @yumcheese

                      At first, I tried running one server but was not able to get it working. I found a tutorial on Youtube (https://www.youtube.com/watch?v=8f13lfnEKY8) which suggests running two servers. I did exactly as he does but my setup fails. I am stuck.

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                      • Y
                        yumcheese
                        last edited by

                        @marvosa said in Clients cannot communicate with each other.:

                        VPNS_A:
                        Type -> Peer to Peer (Shared Key)
                        Port -> 1194
                        Tunnel Network -> 10.0.0.0/24
                        Remote Networks -> 172.16.1.0/24

                        Maybe try adding to your remote networks: 172.16.2.0/24

                        VPNS_B:
                        Type -> Peer to Peer (Shared Key)
                        Port -> 1195
                        Tunnel Network -> 10.0.1.0/24
                        Remote Networks -> 172.16.2.0/24

                        Maybe try adding to your remote networks: 172.16.1.0/24

                        When Branch A (172.16.1.0/24) tries to reach Branch B (172.16.2.0/24), it will send traffic through VPNS_A, but I don't think it knows how to route that request through VPNS_B. Hopefully, those changes will help. I'm relatively new to openvpn, so this might not work. Just trying to help.

                        You might also try the Packet Capture tool under Diagnostics. You can capture the traffic on each tunnel to see where your Pings fail (ICMP). Then you can figure out where to focus your efforts.

                        S 1 Reply Last reply Reply Quote 0
                        • S
                          scilek @yumcheese
                          last edited by

                          @yumcheese

                          It seems to me the solution is to run server on each of the routers and a clients to all other routers.

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                          • Y
                            yumcheese
                            last edited by

                            Actually, I think what I just wrote isn't going to work. If traffic originates in HQ it will not know the proper tunnel to go through if sending traffic to a branch office.

                            S 1 Reply Last reply Reply Quote 0
                            • S
                              scilek @yumcheese
                              last edited by

                              @yumcheese

                              So what is the solution?

                              1 Reply Last reply Reply Quote 0
                              • Y
                                yumcheese
                                last edited by

                                You might need to switch to SSL/TLS instead of pre-shared key and use Client Specific Overrides:
                                https://forum.netgate.com/topic/126091/openvpn-site-to-site-multisite

                                S JeGrJ 2 Replies Last reply Reply Quote 0
                                • S
                                  scilek @yumcheese
                                  last edited by

                                  @yumcheese

                                  I understand. Thank you.

                                  1 Reply Last reply Reply Quote 0
                                  • JeGrJ
                                    JeGr LAYER 8 Moderator @yumcheese
                                    last edited by

                                    @yumcheese said in Clients cannot communicate with each other.:

                                    You might need to switch to SSL/TLS instead of pre-shared key and use Client Specific Overrides:
                                    https://forum.netgate.com/topic/126091/openvpn-site-to-site-multisite

                                    Nope you don't. We have many clients that we do support for, that are using shared-key tunnels from OpenVPN just fine. There's something other missing here. The tunnel itself shouldn't be a problem. For the problem of Site A not being able to Ping Site B and vice versa I'd check the following steps:

                                    • are there rules on the OVPN interface tabs active on any site?
                                    • check routes on HQ and Sites A/B and check if all Sites actually have all required routes set and if the gateways are right.
                                    • check your NAT settings so your VPN tunnel won't get accidentally NATted when it shouldn't

                                    Greets

                                    Don't forget to upvote ๐Ÿ‘ those who kindly offered their time and brainpower to help you!

                                    If you're interested, I'm available to discuss details of German-speaking paid support (for companies) if needed.

                                    S 1 Reply Last reply Reply Quote 1
                                    • S
                                      scilek @JeGr
                                      last edited by

                                      @JeGr

                                      "all required routes"? Are you referring to static routes?

                                      1 Reply Last reply Reply Quote 0
                                      • JeGrJ
                                        JeGr LAYER 8 Moderator
                                        last edited by

                                        @scilek said in Clients cannot communicate with each other.:

                                        "all required routes"? Are you referring to static routes?

                                        Yes, your OVPN configuration as you described in the OP should take care of them and both remote networks (in every location) should show in your system routing table (diagonstics / routes) with the OVPNx interface as Gateway

                                        Don't forget to upvote ๐Ÿ‘ those who kindly offered their time and brainpower to help you!

                                        If you're interested, I'm available to discuss details of German-speaking paid support (for companies) if needed.

                                        S 1 Reply Last reply Reply Quote 0
                                        • S
                                          scilek @JeGr
                                          last edited by

                                          @JeGr

                                          I tried that too, but it did not work. Maybe I was not able to get the hang of it. Could you kindly give an example of a static route entry for the HQ router?

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                                          • JeGrJ
                                            JeGr LAYER 8 Moderator
                                            last edited by JeGr

                                            @scilek said in Clients cannot communicate with each other.:

                                            I tried that too, but it did not work. Maybe I was not able to get the hang of it. Could you kindly give an example of a static route entry for the HQ router?

                                            You tried what? Just have a look into Diagnostics/Routes. If your VPN config is right, there should be routes. Can you show that?

                                            Otherwise as you didn't post any configuration, I can only guess, but as you have to shared key tunnels, you should probably have two OVPN servers defined in your HQ config, so there should be something like ovpns1 and ovpns2 in your routing table. Something along the lines of

                                            172.16.1.1/24	10.0.0.1	UGS	4273856	1500	ovpns1
                                            172.16.2.1/24	10.0.1.1	UGS	4273856	1500	ovpns2
                                            

                                            Don't forget to upvote ๐Ÿ‘ those who kindly offered their time and brainpower to help you!

                                            If you're interested, I'm available to discuss details of German-speaking paid support (for companies) if needed.

                                            S 1 Reply Last reply Reply Quote 0
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