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    VPN throughput dips

    OpenVPN
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    • RicoR
      Rico LAYER 8 Rebel Alliance
      last edited by

      TCP is always a really bad choice for OpenVPN.

      -Rico

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      • chpalmerC
        chpalmer
        last edited by

        What modem are you using?

        Triggering snowflakes one by one..
        Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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        • B
          blwag @chpalmer
          last edited by

          @chpalmer Netgear CM1000. To be clear, I don't see that pattern on LAN traffic. It's only via VPN.

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          • chpalmerC
            chpalmer
            last edited by chpalmer

            How about the other side? How is it built?

            Triggering snowflakes one by one..
            Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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            • B
              blwag @chpalmer
              last edited by

              @chpalmer The source is my office, which is a Cisco/Juniper enterprise environment.

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              • chpalmerC
                chpalmer
                last edited by

                @blwag said in VPN throughput dips:

                192.168.100.1 255.255.255.255

                The above address seems odd.. Can you reach your modem while the VPN is up?

                Triggering snowflakes one by one..
                Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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                • B
                  blwag @chpalmer
                  last edited by

                  @chpalmer Yes, the modem management is accessible via VPN.

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                  • D
                    doylet8456
                    last edited by

                    Hey, I’m seeing exactly the same thing with my OpenVPN server. Were you able to determine the issue ?

                    My video streaming suffers due to the dip. Thanks for showing me the traffic graph package, now I can visually see what I’m seeing onscreen (OLED).

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                    • JKnottJ
                      JKnott @blwag
                      last edited by

                      @blwag said in VPN throughput dips:

                      remote <host> 443 tcp-client

                      why are you using TCP for a VPN? That can cause flow control issues, as both the computer and firewall are trying to do flow control. You should use UDP for VPNs, unless you have no other option.

                      PfSense running on Qotom mini PC
                      i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                      UniFi AC-Lite access point

                      I haven't lost my mind. It's around here...somewhere...

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                      • B
                        blwag @JKnott
                        last edited by

                        @jknott I travel quite a bit for work and outbound network policies seem to differ from office to office. The common denominator is tcp/443. It's the easiest way to know that my VPN will always work.

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                        • B
                          blwag @doylet8456
                          last edited by

                          @doylet8456 I'm currently on Holiday break from work, so I haven't been at the office to do any additional testing. I will after the new year. I haven't found a smoking gun, so my guess is the throughput is the same.

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                          • DerelictD
                            Derelict LAYER 8 Netgate
                            last edited by

                            TCP in TCP is far from ideal, as you are finding out. I would at least test using UDP for the tunnel and see if your issues go away there.

                            Chattanooga, Tennessee, USA
                            A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                            DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                            Do Not Chat For Help! NO_WAN_EGRESS(TM)

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