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

    Problem with TCP and GRE tunnel

    Scheduled Pinned Locked Moved General pfSense Questions
    64 Posts 3 Posters 8.3k 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.
    • 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?

      S 2 Replies Last reply Reply Quote 0
      • K
        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

        1 Reply Last reply Reply Quote 0
        • 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!

          1 Reply Last reply Reply Quote 0
          • S
            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 :/

            1 Reply Last reply Reply Quote 0
            • S
              StomperG @stephenw10
              last edited by StomperG

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

              1 Reply Last reply Reply Quote 0
              • 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?

                S 1 Reply Last reply Reply Quote 0
                • 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.

                  S 1 Reply Last reply Reply Quote 0
                  • S
                    StomperG @stephenw10
                    last edited by

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

                    1 Reply Last reply Reply Quote 0
                    • S
                      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?

                      1 Reply Last reply Reply Quote 0
                      • 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

                        S 1 Reply Last reply Reply Quote 0
                        • S
                          StomperG @stephenw10
                          last edited by

                          @stephenw10

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

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

                          1 Reply Last reply Reply Quote 0
                          • 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.

                            S 1 Reply Last reply Reply Quote 0
                            • S
                              StomperG @stephenw10
                              last edited by

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

                              1 Reply Last reply Reply Quote 0
                              • 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.

                                S 1 Reply Last reply Reply Quote 0
                                • S
                                  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

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

                                    Ok so you should be able to use the VPC WAN address as the target for the client.

                                    S 1 Reply Last reply Reply Quote 0
                                    • S
                                      StomperG @stephenw10
                                      last edited by

                                      @stephenw10
                                      dfa21eb8-9f3c-42e7-baeb-cc5591faa967-image.png

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

                                        Aha, and that could be the problem. That IP is in the same /24 as the local LAN side clients. If you have those set to a /24 subnet it will try to ARP for it directly and fail.

                                        S 1 Reply Last reply Reply Quote 0
                                        • S
                                          StomperG @stephenw10
                                          last edited by

                                          @stephenw10 Uh, im very noob with this sorry, what exacly i need to change?

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

                                            Ok we're back to how the VPC is providing the IPs to you. You have 4 consecutive IPs at the local pf LAN? Including the pf LAN interface address?

                                            The VPC pf WAN address is not consecutive to those?

                                            You probably need to device those into to subnets so routing works correctly.

                                            The routing table at the local pf cannot include the remote side WAN address.

                                            The remote side must be using a smaller subnet than /24 because otherwise connectivity would be completely broken.

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