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    VPN throughput dips

    OpenVPN
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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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        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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            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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                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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                      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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                        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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