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    Problem with TCP and GRE tunnel

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

      Hmm. What happens if you run curl against the webgui at the remote side?

      Or try running an iperf test between the two pf instances.

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      • stephenw10S Online
        stephenw10 Netgate Administrator
        last edited by

        Also try running a pcap on the WAN interface of the local pf when running that same curl test. You should not see any traffic leaving there directly other than the GRE encapsulated traffic.

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          StomperG @stephenw10
          last edited by

          @stephenw10 I already tried to see the traffic on WAN (local pf) and theres no traffic. I will try the other 2 things give me a sec

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          • stephenw10S Online
            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 Online
                  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 Online
                      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 Online
                          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 Online
                                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 Online
                                  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 Online
                                        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 Online
                                            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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