Netgate Discussion Forum
    • Categories
    • Recent
    • Tags
    • Popular
    • Users
    • Search
    • Register
    • Login

    OpenVPN: connecting to LAN subnet

    Scheduled Pinned Locked Moved OpenVPN
    14 Posts 5 Posters 8.1k Views
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • K
      KM
      last edited by

      Hey Folks,

      I have built an ESXi box and am running Pfsense as a virtual machine (among others). I followed many guides on setting up OpenVPN and I can connect remotely. However, I cannot reach any LAN resources other than the pfsense router itself. The LAN is on the 10.0.0.0/24 subnet and the OpenVPN connections are on the 10.0.10.0/24 subnet. From a remotely connected client I can ping 10.0.0.1 (pfsense) with an IP of 10.0.10.6 but I can't ping any of my other servers on the 10.0.0.0 subnet.

      Is there anything I should check?
      Thanks.

      1 Reply Last reply Reply Quote 0
      • N
        Nachtfalke
        last edited by

        The OpenVPN server needs to push the rout of the LAn subnet to the client.

        
        push "Route 10.0.0.0 255.255.255.0";
        
        

        The Firewall rule on OpenVPN tab must be setup correct.

        1 Reply Last reply Reply Quote 0
        • K
          KM
          last edited by

          I have the push "route 10.0.0.0 255.255.255.0" created on the server, although I think this is already created through the wizard. There is also a pass firewall rule under the openvpn tab, which was also created with the wizard.

          Actually, when I connect the remote client without the "push route…." there are no errors on the OpenVPN client dialog, but when I add it, it says "route addition failed... : the object already exists" and connects successfully. This is why I assumed that PFsense created that route automatically.

          1 Reply Last reply Reply Quote 0
          • N
            Nachtfalke
            last edited by

            Didn't use the wizard for that so I had to manually add these routes in my environment.
            If the route exists and the firewall rule allows the traffic then there is another problem.

            Check the firewall on the destination host on LAN subnet - better disable the firewall for testing.

            Do you run the OpenVPN client on a Windows 7 machine ? If yes - run it "As administrator". But you probably did that because it added the route.

            1 Reply Last reply Reply Quote 0
            • K
              KM
              last edited by

              Here is a copy of my route table. I'm not sure if this is right or not.

              IPv4
              Destination Gateway        Netif
              default 142.177.. em0
              10.0.0.0/24 link#2                em1
              10.0.0.1 link#2                lo0
              10.0.10.0/24 10.0.10.2 ovpns1
              10.0.10.1 link#8         lo0
              10.0.10.2 link#8         ovpns1
              127.0.0.1 link#4         lo0
              142.177../22 link#1 em0
              142.177.. link#1 lo0

              1 Reply Last reply Reply Quote 0
              • K
                KM
                last edited by

                While playing around I found something interesting. As I mentioned pfsense is running as a VM inside an ESXi host. From the VPN connected computer (10.0.10.6) I can ping 10.0.0.1 which is pfsense, but I can also ping 10.0.0.2, which is the esxi host, but none of the machines past that. I just thought this was odd.

                1 Reply Last reply Reply Quote 0
                • K
                  KM
                  last edited by

                  Some more interesting things:
                  On a hunch I decided to add a route from one of the devices on the 10.0.0.0 subnet to the 10.0.10.0 subnet to see if that would help. Previously a ping from 10.0.10.6 to 10.0.0.5 (for example) resulted in a request timeout and a ping from 10.0.0.9 to 10.0.10.6 resulted in a destination unreachable reply.

                  So, on my 10.0.0.9 machine I opened a command prompt with the following command: route ADD 10.0.10.0 MASK 255.255.255.0 10.0.0.1 METRIC 266
                  To my surprise this allowed pings to pass both ways. I'll keep you updated, but I'm not really sure why this would make a difference given the routes already present on the machines.

                  1 Reply Last reply Reply Quote 0
                  • M
                    marvosa
                    last edited by

                    Post server config and post client routing table once connected.

                    A screen shot of the firewall rule from openvpn tab would also be helpful.

                    1 Reply Last reply Reply Quote 0
                    • N
                      Nachtfalke
                      last edited by

                      @KM:
                      As marvosa said, please post the client routing tabel. On Windows you can find this with "netstat -rn"

                      1 Reply Last reply Reply Quote 0
                      • M
                        Metu69salemi
                        last edited by

                        or with```
                        route print

                        1 Reply Last reply Reply Quote 0
                        • K
                          KM
                          last edited by

                          This is after a reboot of the machine. The route is gone because I didn't add it as persistent. The default gateway is set as 10.0.0.1 on this machine in the adapter config settings.

                          route print
                          IPv4 Route Table
                          ===========================================================================
                          Active Routes:
                          Network Destination        Netmask          Gateway      Interface  Metric
                                    0.0.0.0          0.0.0.0        10.0.0.1        10.0.0.9    266
                                  10.0.0.0        255.0.0.0        On-link          10.0.0.9    266
                                  10.0.0.9  255.255.255.255        On-link          10.0.0.9    266
                            10.255.255.255  255.255.255.255        On-link          10.0.0.9    266
                                  127.0.0.0        255.0.0.0        On-link        127.0.0.1    306
                                  127.0.0.1  255.255.255.255        On-link        127.0.0.1    306
                            127.255.255.255  255.255.255.255        On-link        127.0.0.1    306
                                  224.0.0.0        240.0.0.0        On-link        127.0.0.1    306
                                  224.0.0.0        240.0.0.0        On-link          10.0.0.9    266
                            255.255.255.255  255.255.255.255        On-link        127.0.0.1    306
                            255.255.255.255  255.255.255.255        On-link          10.0.0.9    266
                          ===========================================================================
                          Persistent Routes:
                            Network Address          Netmask  Gateway Address  Metric
                                    0.0.0.0          0.0.0.0        10.0.0.1  Default
                          ===========================================================================

                          1 Reply Last reply Reply Quote 0
                          • K
                            KM
                            last edited by

                            This is after OpenVPN client is connected:

                            IPv4 Route Table

                            Active Routes:
                            Network Destination        Netmask          Gateway      Interface  Metric
                                      0.0.0.0          0.0.0.0        10.0.0.1        10.0.0.9    266
                                    10.0.0.0        255.0.0.0        On-link          10.0.0.9    266
                                    10.0.0.0    255.255.255.0        10.0.10.5        10.0.10.6    30
                                    10.0.0.9  255.255.255.255        On-link          10.0.0.9    266
                                    10.0.10.1  255.255.255.255        10.0.10.5        10.0.10.6    30
                                    10.0.10.4  255.255.255.252        On-link        10.0.10.6    286
                                    10.0.10.6  255.255.255.255        On-link        10.0.10.6    286
                                    10.0.10.7  255.255.255.255        On-link        10.0.10.6    286
                              10.255.255.255  255.255.255.255        On-link          10.0.0.9    266
                                    127.0.0.0        255.0.0.0        On-link        127.0.0.1    306
                                    127.0.0.1  255.255.255.255        On-link        127.0.0.1    306
                              127.255.255.255  255.255.255.255        On-link        127.0.0.1    306
                                    224.0.0.0        240.0.0.0        On-link        127.0.0.1    306
                                    224.0.0.0        240.0.0.0        On-link        10.0.10.6    286
                                    224.0.0.0        240.0.0.0        On-link          10.0.0.9    266
                              255.255.255.255  255.255.255.255        On-link        127.0.0.1    306
                              255.255.255.255  255.255.255.255        On-link        10.0.10.6    286
                              255.255.255.255  255.255.255.255        On-link          10.0.0.9    266

                            Persistent Routes:
                              Network Address          Netmask  Gateway Address  Metric
                                      0.0.0.0          0.0.0.0        10.0.0.1  Default

                            1 Reply Last reply Reply Quote 0
                            • M
                              marvosa
                              last edited by

                              Please post your tunnel settings.  Are you routed or bridged?

                              1 Reply Last reply Reply Quote 0
                              • P
                                phil.davis
                                last edited by

                                This line looks like a problem:

                                10.0.0.0        255.0.0.0         On-link          10.0.0.9    266
                                

                                Your 10.0.0.9 interface (on your server, if I understood the descriptions correctly) is thinking that it is sitting on a 10.0.0.0/8 network. So when it replies to any 10.n.n.n addresses, it will think it can reach them directly on its local LAN. It should be in the 10.0.0.0/24 network. Then it will send packets for 10.0.10.0/24 network addresses to the router.

                                As the Greek philosopher Isosceles used to say, "There are 3 sides to every triangle."
                                If I helped you, then help someone else - buy someone a gift from the INF catalog http://secure.inf.org/gifts/usd/

                                1 Reply Last reply Reply Quote 0
                                • First post
                                  Last post
                                Copyright 2025 Rubicon Communications LLC (Netgate). All rights reserved.