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    Using a GRE Tunnel to route VMs network and IP to external network.

    Scheduled Pinned Locked Moved General pfSense Questions
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    • XuapX
      Xuap @stephenw10
      last edited by

      @stephenw10 The NAT rules on the remote site are like this:

      1:1
      475677e5-4214-4e4e-b611-55973f5b02f6-image.png

      Outbound
      5a5b6fb3-7c54-4697-b61a-3499629693bb-image.png

      Yeah, basically it just doesn't have internet access, nor even access to the pfsense or tunnel ping.. I can't ping the tunnel through the VM even tho the ping arrives there.

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

        Ok the 1:1 NAT rule should be on WAN with the external IP being the public IP VIP and the internal IP being the private IP of the server.

        XuapX 1 Reply Last reply Reply Quote 0
        • XuapX
          Xuap @stephenw10
          last edited by

          @stephenw10 So, like this?
          c6187a6d-ca16-44d6-a4e3-28daa7645360-image.png

          And on the VM, like this?
          489184d9-f0b5-4787-b6f7-3734c69eb06f-image.png

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

            No the external IP should be the public IP. The internal IP should be the server IP in 192.168.1.0/24.

            The VM gateway needs to be in the subnet so it should be the local pfSense VLAN interface IP. Probably 192.168.1.1

            XuapX 1 Reply Last reply Reply Quote 0
            • XuapX
              Xuap @stephenw10
              last edited by

              @stephenw10 So, my networks on local pfsense are like this:

              7167937f-2f66-45c0-834b-a080d152ce26-image.png

              My WAN is the 192.168.1.10 which is on the main gateway of the router 192.168.1.254

              I use the VLAN as a bridge for the VMs, but should I use something else both on pfsense or on the VMs?

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

                Hmm, where is the VM at 192.168.1.86 then?

                I expect all the VMs to be in the VLAN subnet and all the routing the NAT setup to be to and from the VLAN subnet.

                Steve

                XuapX 1 Reply Last reply Reply Quote 0
                • XuapX
                  Xuap @Xuap
                  last edited by

                  I also did a pcap on both the GRE and VLAN of the local pfsense

                  GRE:
                  d14dbcf6-36b0-4e74-bf2d-eb48e440fa4e-image.png

                  VLAN:
                  f19055c3-ebf6-4091-b462-8ac72173b942-image.png

                  So, as I understood it is sending the ping to the 1.1.1.1 but it is not receiving any traffic..

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

                    Right, well it won't if traffic from 192.168.1.86 is coming in on the wrong interface!

                    If you run a pcap on WAN you will see all the replies going back that way because that's where the 192.168.1.0/24 subnet is.

                    How exactly is the VM connected?

                    XuapX 1 Reply Last reply Reply Quote 0
                    • XuapX
                      Xuap @stephenw10
                      last edited by

                      @stephenw10 The VM is in the proxmox with the IP on 192.168.1.86 and gateway 192.168.2.1 like I showed above

                      The VM is with the bridge of the VLAN (192.168.2.1) which is the Linux Bridge 1 on proxmox (vmbr1) that will (supposedly) be attached to all VMs so it can tunnel the traffic to the remote pfsense

                      1 Reply Last reply Reply Quote 0
                      • XuapX
                        Xuap @stephenw10
                        last edited by

                        @stephenw10 16249c88-5c5c-499c-8067-7e1321555bac-image.png

                        This is the only 1.1.1.1 ping I have on the WAN of the local pfsense

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                        • stephenw10S
                          stephenw10 Netgate Administrator
                          last edited by

                          There is an ARP request for 192.168.1.86 though because it's trying to find it on the WAN. And failing.

                          The VMs should be in the VLAN subnet, 192.168.2.0/24.

                          The static route at the remote end should be for that subnet.

                          The 1:1 NAT rules at the remote side should also be for host in that subnet.

                          Steve

                          XuapX 1 Reply Last reply Reply Quote 0
                          • XuapX
                            Xuap @stephenw10
                            last edited by

                            @stephenw10 So, like this?

                            8d412b2e-cc2e-4ae2-af56-207db7d0cc09-image.png
                            2e9705b1-00cb-4abb-825d-211ac6e37fa8-image.png
                            9a1a6a0a-5063-4887-9df4-4ba4b4ead7ce-image.png

                            XuapX 1 Reply Last reply Reply Quote 0
                            • XuapX
                              Xuap @Xuap
                              last edited by

                              Ok, so It looks like I was using a 192.168.1.86 on a .2 subnet, I changed it to 192.168.2.86 and it now pings 1.1.1.1 and 8.8.8.8 and the tunnel, but doesn't have internet access to like ifconfig.me or google.com. I'll do a bit more testing, but it's closer than never to work out.

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

                                Yeah you need to be using 192.168.2.X everywhere.

                                You are probably seeing pings work but no other traffic because there is some asymmetry somewhere. Once all the rules and routes are changed to the VLAN subnet it should work.

                                XuapX 1 Reply Last reply Reply Quote 0
                                • XuapX
                                  Xuap @stephenw10
                                  last edited by

                                  @stephenw10 Ok, it is pinging now. I can ping everything on IP addresses, except domains. Like, If I ping my Home Public IP address, I get a ping of 20ms or something, when the tunnel's ping is about 9ms.

                                  But is it normal the ping state is 0:0 on both ends?

                                  Local:
                                  1cb08819-1b8b-4ac5-a45b-dfbe311348f1-image.png

                                  Remote:
                                  80fcbc34-bdfe-4b60-b3d2-91adf9b2b878-image.png

                                  Also the only NAT rules I have are on the remote pfsense, which are:
                                  ff35e59a-2ab5-4dfb-a6b2-81dc147ac867-image.png

                                  On the local pfsense I have the NAT disabled.

                                  What rules should I change/add?

                                  XuapX stephenw10S 2 Replies Last reply Reply Quote 0
                                  • XuapX
                                    Xuap @Xuap
                                    last edited by

                                    Also, traceroutes only give * * * * back:

                                    27620e86-8dd4-4046-bfaa-bb66713b3f4d-image.png

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                                    • stephenw10S
                                      stephenw10 Netgate Administrator @Xuap
                                      last edited by

                                      @xuap said in Using a GRE Tunnel to route VMs network and IP to external network.:

                                      But is it normal the ping state is 0:0 on both ends?

                                      Yes. icmpv4 doesn't have a state.

                                      You should still have 1:1 NAT rules on the remote pfSense. With that you wouldn't need the outbound NAT rule, the 1:1 does that already.
                                      And you need the 1:1 rule if you want inbound connections the VM to work. Or add port forwards for each connection you need but 1:1 does it all.

                                      Steve

                                      XuapX 1 Reply Last reply Reply Quote 0
                                      • XuapX
                                        Xuap @stephenw10
                                        last edited by

                                        @stephenw10 So, I can remove the NAT Rules and set NAT as automatic because 1:1 Mapping does all those rules already?

                                        Also, I want to use inbound connections too, for that, I do need that rule mentioned above, or what should I do?

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                                        • stephenw10S
                                          stephenw10 Netgate Administrator
                                          last edited by

                                          Yes, if you have the 1:1 NAT rule in place it NAT's all traffic inbound and outbound between those IPs, 1:1.
                                          So you can remove/disable the outbound NAT rule. No harm in leaving it in hybrid mode though.

                                          For inbound traffic you still need firewall rules to allow that on the remote side WAN. And they re applied after NAT so the destination will be the internal private IPs of the VMs.

                                          XuapX 1 Reply Last reply Reply Quote 0
                                          • XuapX
                                            Xuap @stephenw10
                                            last edited by

                                            @stephenw10 I putted NAT in auto mode
                                            b0647163-4fde-462a-90da-995f9ebce5e5-image.png
                                            and in the WAN rules I have this
                                            c9dc6e49-f282-4b31-ab0c-2a8f703dc952-image.png

                                            you were referring to those rules I just created right?

                                            I can ping any IP address, but I can't ping any URL
                                            20acf6c1-66b6-405a-bdf7-d8a834301eb0-image.png

                                            I have the nameservers 8.8.8.8 and 8.8.4.4 on the VM

                                            1 Reply Last reply Reply Quote 0
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