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    Problem with TCP and GRE tunnel

    Scheduled Pinned Locked Moved General pfSense Questions
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    • stephenw10S
      stephenw10 Netgate Administrator
      last edited by

      The other thing to test would be a pcap on both WANs at the same time so you can check if GRE packets are leaving the local WAN and just not arriving at the remote WAN. I.E. is it an actual problem in the route somewhere.

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        StomperG @stephenw10
        last edited by

        @stephenw10 I can curl without problems on the remote one. Also how can i do a iperf?

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          StomperG @stephenw10
          last edited by StomperG

          @stephenw10 I did it now and theres no logs on the local side (WAN) while doing a pcap

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          • stephenw10S
            stephenw10 Netgate Administrator
            last edited by

            iperf is a package you can install in the gui. You can also install just the backend pkg at the command line if you want.

            @StomperG said in Problem with TCP and GRE tunnel:

            I did it now and theres no logs on the local side (WAN) while doing a pcap

            So the local side isn't actually sending GRE packets even though the pcap on the GRE interface shows them?

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              StomperG @stephenw10
              last edited by

              @stephenw10 At least the WAN pcap on the local dont show anything

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              • stephenw10S
                stephenw10 Netgate Administrator
                last edited by

                Nothing at all? It must show the GRE packets if the curl command succeeds. Or do you mean just during the unexpected delay?

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                  Konstanti @StomperG
                  last edited by Konstanti

                  @StomperG

                  Hi
                  maybe this will help
                  I don't remember why I set up the rules this way (I think I read it in some article), but
                  1 GRE interface (MSS 1380)
                  2 created this floating rule for GRE interface (TUN100)

                  2905ff65-7d7b-44ad-886b-194a33695453-image.png

                  5f98e495-11ba-4640-9423-b5f92765c0ba-image.png

                  7bdb0851-9887-4081-8261-86ebdd87988a-image.png

                  here is an example of the information transfer rate through a tunnel with these settings

                  d5ea36cd-2932-4b0b-841b-aca9563b9b03-image.png

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                  • stephenw10S
                    stephenw10 Netgate Administrator
                    last edited by stephenw10

                    That can be required for GRE+IPSec transport. Although there is now an option to allow it without that: https://redmine.pfsense.org/issues/12289

                    However in that situation the initial handshake would fail. And that shouldn't apply here because it's not encrypted. But....anything's possible!

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                      StomperG @stephenw10
                      last edited by StomperG

                      @stephenw10 Hey that's for the local or remote pf? I tried on local and had the same result :/

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                        StomperG @stephenw10
                        last edited by StomperG

                        @stephenw10 Nothing at all on the local WAN
                        Never did an iperf, is there any topic for that?

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                        • stephenw10S
                          stephenw10 Netgate Administrator
                          last edited by

                          Yeah I wouldn't expect it to make any difference there because you're not using IPSec transport.

                          To my earlier question; do you really see no GRE packets in the pcap on the local WAN? Or just during the gap?

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                          • stephenw10S
                            stephenw10 Netgate Administrator
                            last edited by

                            At the command line on each end you can run iperf3. So run iperf3 -s to start a server at one end. Then iperf3 -c <server IP> at the other.

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                              StomperG @stephenw10
                              last edited by

                              @stephenw10 On the local WAN i literally see 0 lines of logs during de pcap

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                                StomperG @stephenw10
                                last edited by StomperG

                                @stephenw10 I just need to run this 2 commands and wait? Or did i need to do something else on the VM with the problem? And the server IP is the GRE IP right?

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                                • stephenw10S
                                  stephenw10 Netgate Administrator
                                  last edited by

                                  Hmm, are you filtering the pcap on the local pf?

                                  Yes the server side runs continually until you kill it. The client will run for 30s by default.
                                  https://man.freebsd.org/cgi/man.cgi?query=iperf3

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                                    StomperG @stephenw10
                                    last edited by

                                    @stephenw10

                                    Server:
                                    46876a21-edd6-4780-a8e7-19f8d544cf79-image.png

                                    Client:
                                    7c51ef3c-a7fa-4f77-927c-797f85719014-image.png

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                                    • stephenw10S
                                      stephenw10 Netgate Administrator
                                      last edited by

                                      Hmm, same both ways?

                                      Try using one of the other IPs on the server as the target. The GRE endpoint IP can behave in an odd way.

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                                        StomperG @stephenw10
                                        last edited by

                                        @stephenw10 I tried but or give me firewall problem because the port isnt exposed or give me that

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                                        • stephenw10S
                                          stephenw10 Netgate Administrator
                                          last edited by

                                          Which way are you testing? The server end should listen on all available IPs by default. I would expect the client end to have a route to any of them.

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                                            StomperG @stephenw10
                                            last edited by

                                            @stephenw10 Im starting the server on the VPC (from the company where i bought the IP's and VPC) and client on the local pf VM

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