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    pfSense -> OpenVPN Ubuntu site-to-site throubleshooting help

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    • KpuCkoK
      KpuCko
      last edited by

      Ok, thanks to all of you guys.

      I will find some time today to show the config of the OpenVPN server with all the routes and CCDs. Just bear with me, there are a lot of things happening in parallel.

      1 Reply Last reply Reply Quote 0
      • KpuCkoK
        KpuCko
        last edited by KpuCko

        Here it is:

        root@frax1021dckr1110:~# cat /etc/openvpn/chroot/frax1021dckr1110/ccd/sofn1010fw301
        
        ifconfig-push 172.16.21.10 255.255.255.0
        
        push "route 10.0.1.10 255.255.255.0"
        
        iroute 192.168.0.0 255.255.255.0
        root@frax1021dckr1110:~#
        

        And the OpenVPN server config:

        # Service user and group
        user nobody
        group nogroup
        
        # Set output verbosity
        verb 3
        
        # Tunnel config
        proto udp
        dev tun
        port 1194
        compress stub-v2
        chroot /etc/openvpn/chroot/frax1021dckr1110/
        tmp-dir tmp/
        client-config-dir ccd
        ccd-exclusive
        
        persist-tun
        persist-key
        
        # Server config
        topology subnet
        server 172.16.21.0 255.255.255.0
        tls-server
        tls-version-min 1.3
        ncp-ciphers AES-256-GCM
        dh /etc/easyrsa/pki/dh.pem
        ca /etc/easyrsa/pki/ca.crt
        cert /etc/easyrsa/pki/issued/frax1021dckr1110.crt
        key  /etc/easyrsa/pki/private/frax1021dckr1110.key
        crl-verify crl.pem
        verify-client-cert require
        tls-auth /etc/openvpn/private/frax1021dckr1110-ta.key 0
        auth SHA256
        keepalive 10 60
        float
        
        #
        # Extra params
        #
        
        root@frax1021dckr1110:~#
        

        There is no static route for 192.168.0.0/24 on the server side:

        root@frax1021dckr1110:~# route -n | grep 192.168
        192.168.192.0   172.25.0.1      255.255.255.0   UG    20     0        0 tun0
        192.168.193.0   172.25.0.1      255.255.255.0   UG    20     0        0 tun0
        root@frax1021dckr1110:~#
        

        So now you want me to put this on the server config?

        route 192.168.0.0 255.255.255.0
        

        And we are done?

        Meantime let me share the rules for that interface:

        37ec8fb8-3d93-46ed-a7d0-455ace4dd0e0-image.png

        Maybe this also make sense:

        1ba31dd3-096a-4dbf-b5f4-7312379b1b93-image.png

        This is the config part of the OpenVPN client from the pfSense perspective

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

          @kpucko said in pfSense -> OpenVPN Ubuntu site-to-site throubleshooting help:

          o now you want me to put this on the server config?
          route 192.168.0.0 255.255.255.0

          And we are done?

          At least this is necessary to get it work.

          Meantime let me share the rules for that interface:

          Consider, the "VPNFRAX1 net" is only the tunnel (transit) network. This only applies to the server itself.
          But as I got your initial post, you want to set up a site-to-site VPN. So I assume you need access from behind the Ubuntu server, don't you?
          If yes, you have also ensure that there is a route for the clients Lan on the server side pointing the the server (in case the Ubuntu is not the default gateway).

          Maybe this also make sense:

          If you want to communicate with the network(s) behind the Ubuntu you have to add them to the "Remote networks" here.

          stephenw10S 1 Reply Last reply Reply Quote 1
          • stephenw10S
            stephenw10 Netgate Administrator @viragomann
            last edited by stephenw10

            @viragomann said in pfSense -> OpenVPN Ubuntu site-to-site throubleshooting help:

            If you want to communicate with the network(s) behind the Ubuntu you have to add them to the "Remote networks" here.

            It's an SSL/TLS server so it should push those networks to the client(s).
            And it looks like it is configured to push 10.0.1.10/24. That should be 10.0.1.0/24 bu will probably still work.

            Yes, those firewall rules will block everything except ping and BGP in the server to client direction. That might be what you want though.

            Steve

            V 1 Reply Last reply Reply Quote 1
            • V
              viragomann @stephenw10
              last edited by

              @stephenw10 said in pfSense -> OpenVPN Ubuntu site-to-site throubleshooting help:

              It's an SSL/TLS server so it should push those networks to the client(s).
              And it looks like it is configured to push 10.0.1.10/24. That should be 10.0.1.0/24 bu will probably still work.

              Ahh, you're right.
              I noticed this above.

              1 Reply Last reply Reply Quote 1
              • KpuCkoK
                KpuCko
                last edited by KpuCko

                @viragomann said in pfSense -> OpenVPN Ubuntu site-to-site throubleshooting help:

                route 192.168.0.0 255.255.255.0

                Yeah :-) all good now
                Thanks guys!!! Everything is up and running.

                Will leave the config here in case if anyone wonder howto do it:

                root@frax1021dckr1110:~# grep route /etc/openvpn/server/frax1021dckr1110.conf
                route 192.168.0.0 255.255.255.0
                root@frax1021dckr1110:~# cat /etc/openvpn/chroot/frax1021dckr1110/ccd/sofn1010fw301
                
                ifconfig-push 172.16.21.10 255.255.255.0
                
                push "route 10.0.1.10 255.255.255.0"
                
                iroute 192.168.0.0 255.255.255.0
                root@frax1021dckr1110:~#
                

                The tests:

                C:\Users\KpuCko>ipconfig |FIND "192.168.0.15"
                   IPv4 Address. . . . . . . . . . . : 192.168.0.15
                
                C:\Users\KpuCko>ping 10.0.1.10
                
                Pinging 10.0.1.10 with 32 bytes of data:
                Reply from 10.0.1.10: bytes=32 time=30ms TTL=63
                Reply from 10.0.1.10: bytes=32 time=30ms TTL=63
                Reply from 10.0.1.10: bytes=32 time=30ms TTL=63
                Reply from 10.0.1.10: bytes=32 time=30ms TTL=63
                

                The confusing part for me was this route and iroute settings. I read in the tutorial linked above that they both are needed, check here:

                Why the redundant route and iroute statements, you might ask? The reason is that route controls the routing from the kernel to the OpenVPN server (via the TUN interface) while iroute controls the routing from the OpenVPN server to the remote clients. Both are necessary.

                The only thing left unclear for me is the line with the pool, check this:

                Oct 10 05:54:14 frax1021dckr1110 openvpn[61734]: Could not determine IPv4/IPv6 protocol. Using AF_INET
                Oct 10 05:54:14 frax1021dckr1110 openvpn[61734]: Socket Buffers: R=[212992->212992] S=[212992->212992]
                Oct 10 05:54:14 frax1021dckr1110 openvpn[61734]: UDPv4 link local (bound): [AF_INET][undef]:1194
                Oct 10 05:54:14 frax1021dckr1110 openvpn[61734]: UDPv4 link remote: [AF_UNSPEC]
                Oct 10 05:54:14 frax1021dckr1110 openvpn[61734]: chroot to '/etc/openvpn/chroot/frax1021dckr1110/' and cd to '/' succeeded
                Oct 10 05:54:14 frax1021dckr1110 openvpn[61734]: GID set to nogroup
                Oct 10 05:54:14 frax1021dckr1110 openvpn[61734]: UID set to nobody
                Oct 10 05:54:14 frax1021dckr1110 openvpn[61734]: MULTI: multi_init called, r=256 v=256
                Oct 10 05:54:14 frax1021dckr1110 openvpn[61734]: IFCONFIG POOL IPv4: base=172.16.21.2 size=253
                Oct 10 05:54:14 frax1021dckr1110 openvpn[61734]: Initialization Sequence Completed
                

                So the pool starts from 172.16.21.2 because 172.16.21.1 is reserved for the local IP, but the client is instructed via CCD to get 172.16.21.10 which is shown below:

                Oct 10 05:54:51 frax1021dckr1110 openvpn[61734]: sofn1010fw301:63268 MULTI_sva: pool returned IPv4=172.16.21.2, IPv6=(Not enabled)
                Oct 10 05:54:51 frax1021dckr1110 openvpn[61734]: sofn1010fw301/:63268 OPTIONS IMPORT: reading client specific options from: ccd/sofn1010fw301
                Oct 10 05:54:51 frax1021dckr1110 openvpn[61734]: sofn1010fw301:63268 MULTI: Learn: 172.16.21.10 -> sofn1010fw301:63268
                Oct 10 05:54:51 frax1021dckr1110 openvpn[61734]: sofn1010fw301:63268 MULTI: primary virtual IP for sofn1010fw301:63268: 172.16.21.10
                Oct 10 05:54:51 frax1021dckr1110 openvpn[61734]: sofn1010fw301:63268 MULTI: internal route 192.168.0.0/24 -> sofn1010fw301:63268
                Oct 10 05:54:51 frax1021dckr1110 openvpn[61734]: sofn1010fw301:63268 MULTI: Learn: 192.168.0.0/24 -> sofn1010fw301:63268
                Oct 10 05:54:51 frax1021dckr1110 openvpn[61734]: sofn1010fw301:63268 Data Channel: using negotiated cipher 'AES-256-GCM'
                Oct 10 05:54:51 frax1021dckr1110 openvpn[61734]: sofn1010fw301:63268 Outgoing Data Channel: Cipher 'AES-256-GCM' initialized with 256 bit key
                Oct 10 05:54:51 frax1021dckr1110 openvpn[61734]: sofn1010fw301:63268 Incoming Data Channel: Cipher 'AES-256-GCM' initialized with 256 bit key
                Oct 10 05:54:51 frax1021dckr1110 openvpn[61734]: sofn1010fw301:63268 SENT CONTROL [sofn1010fw301]: 'PUSH_REPLY,route-gateway 172.16.21.1,topology subnet,ping 10,ping-restart 60,route 10.0.1.10 255.255.255.0,ifconfig 172.16.21.10 255.255.255.0,peer-id 0,cipher AES-256-GCM' (status=1)
                

                Great 172.16.21.10 is assigned to the client, but see the local kernel routing table:

                root@frax1021dckr1110:~# route -n |grep 192.168
                192.168.0.0     172.16.21.2     255.255.255.0   UG    0      0        0 tun1
                root@frax1021dckr1110:~#
                

                Why 172.16.21.2, I don't have 172.16.21.2 anywhere..
                At least it works, so I'm asking just for clarity :-)

                1 Reply Last reply Reply Quote 0
                • stephenw10S
                  stephenw10 Netgate Administrator
                  last edited by

                  OpenVPN always uses the first IP in the tunnel subnet to route traffic to like that. But usually at the server end. I expect to see .1 there at the client side if the server is configured as that. It seems to be passing that as a gateway.

                  It doesn't really matter since it's actually the OpenVPN daemon that decides where to route it to. The kernel route only has to get it to the daemon.

                  You should change the local subnet you are pushing to 10.0.1.0/24 instead of .10 to be 'correct'. Some clients might reject that as an invalid route.

                  Steve

                  KpuCkoK 1 Reply Last reply Reply Quote 1
                  • KpuCkoK
                    KpuCko @stephenw10
                    last edited by

                    @stephenw10

                    You should change the local subnet you are pushing to 10.0.1.0/24 instead of .10 to be 'correct'. Some clients might reject that as an invalid route.

                    Steve

                    Oo I see what you are speaking about:

                    push "route 10.0.1.10 255.255.255.0"
                    

                    It should be 10.0.0.0 255.255.255.0, I even haven't noticed that I wrote it in this way..

                    stephenw10S 1 Reply Last reply Reply Quote 0
                    • stephenw10S
                      stephenw10 Netgate Administrator @KpuCko
                      last edited by

                      It should be: 10.0.1.0 255.255.255.0

                      KpuCkoK 1 Reply Last reply Reply Quote 1
                      • KpuCkoK
                        KpuCko @stephenw10
                        last edited by

                        @stephenw10 said in pfSense -> OpenVPN Ubuntu site-to-site throubleshooting help:

                        It should be: 10.0.1.0 255.255.255.0

                        Of course :-)))

                        Sorry about that, I have really fast fingers =]]

                        1 Reply Last reply Reply Quote 1
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