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    OpenVPN Site to Site VPN: No LAN to LAN Communication

    Scheduled Pinned Locked Moved OpenVPN
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    • T
      Teh_Bot
      last edited by

      Hi all,

      I have two sites:

      A) LAN: 12.1.1.0/24 (server)
      B) LAN: 11.1.1.0/24 (client)

      Tunnel Address: 192.168.50.0/24

      At this moment, I have the site to site VPN up; however, two LANs can't communicate with each other.

      Here is the odd part (...i think), both pfSense box itself can reach the LANs (example, box A can reach LAN of box B) only if I source the traffic from the new tunnel interface (OPT1 for example). If I source from LAN interface, no luck.

      I verified that followings were taken care of:

      1. Firewall rules. Under LAN/OpenVPN/OPT1 all pretty much allow any any
      2. I tried Outbound NAT as some threads suggested, no luck.
      3. Routing seems to be okay:

      Destination Gateway Flags Use Mtu Netif Expire
      default 192.168.1.1 UGS 412450 1500 igb0
      11.1.1.0/24 link#2 U 346097 1500 igb1
      11.1.1.1 link#2 UHS 258 16384 lo0
      12.1.1.0/24 192.168.50.1 UGS 790 1500 ovpnc1
      127.0.0.1 link#4 UH 97 16384 lo0
      192.168.1.0/24 link#1 U 134359 1500 igb0
      192.168.1.68 link#1 UHS 0 16384 lo0
      192.168.50.1 link#8 UH 251091 1500 ovpnc1
      192.168.50.2 link#8 UHS 0 16384 lo0

      1. I even added static routes on both sides. Here is an example on client box:

      12.1.1.0/24 OPT1_VPNV4 - 192.168.50.1 OPT1

      What else am I missing? Let me know if you need more information.

      Thanks,

      1 Reply Last reply Reply Quote 0
      • RicoR
        Rico LAYER 8 Rebel Alliance
        last edited by

        Are you really using 12.1.1.0/24 and 11.1.1.0/24 or did you obfuscate the address space?

        -Rico

        T bingo600B 2 Replies Last reply Reply Quote 0
        • N
          netblues
          last edited by

          Apart from the invalid address space, openvpn has its own internal routing table too
          You need to specify the networks behind the clients
          something like that
          630ea15b-cdcd-43a9-98d2-354499b4c9bf-image.png

          T 1 Reply Last reply Reply Quote 0
          • T
            Teh_Bot @Rico
            last edited by

            @Rico Hi Rico,

            I am actually using 12.1.1.0/24 and 11.1.1.0/24 on the LAN side. Lets just say this is the network I adopted. I have over 20 locations where I want to place Netgate firewall and doing proof of concept at this moment to see if its feasible.

            Since I am using odd addressing space, is this the reason why my two LANs having issues?

            1 Reply Last reply Reply Quote 0
            • T
              Teh_Bot @netblues
              last edited by

              @netblues Hi ,

              Thanks for the feedback! I haven't tried that. I only have 12.1.1.0/24 & 11.1.1.0/24 as remote network.

              1 Reply Last reply Reply Quote 0
              • T
                Teh_Bot
                last edited by

                So guys,

                I was able to resolve the issue by switching the network to private addresses (i.e. 12.1.1.0/24 -- > 10.12.12.0/24) and by adding static routes.

                I am not sure why I wasn't able to route 12.1.1.0/24 even with static routes properly. Currently, its working flawlessly with Cisco ASAs and I am planning on migrating over 20 sites to Netgate.

                Any suggestions? Is it even possible to route public networks via internal VPN cloud?

                Thanks,

                N 1 Reply Last reply Reply Quote 0
                • N
                  netblues @Teh_Bot
                  last edited by

                  @Teh_Bot openvpn or any other vpn technology isn't automatically filtering on any ip's (with a very few exceptions, like localhost, sometimes apipa etc)
                  Still, you need to declare to vpns the ranges that will pass through.
                  See the openvpn wiki entry
                  https://community.openvpn.net/openvpn/wiki/RoutedLans

                  putting nat rules in a vpn is not recommended, and it does make things difficult to comprehend.

                  I suspect there was some typo somewhere and was eliminated by renumbering.

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

                    If you needed static routes to make this work you did it wrong. You will experience occasional strange issues if you use static routes.

                    Let OpenVPN install the routes using the Remote Networks fields.

                    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 1
                    • bingo600B
                      bingo600 @Rico
                      last edited by

                      This post is deleted!
                      1 Reply Last reply Reply Quote 0
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