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    OpenVPN MTU

    Scheduled Pinned Locked Moved OpenVPN
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    • JKnottJ
      JKnott
      last edited by

      I was just experimenting with packet size through OpenVPN. The OpenVPN MTU is shown as 1500 on both pfSense and Linux ends of the VPN. Of course, this is not possible due to the OpenVPN headers, which reduce the MTU available to traffic. Testing with different size pings verifies this. Why do the tunnel endpoints show a bigger MTU than can be used? With IPv4, the oversize pings get fragmented, but on IPv6, they don't get through at all.

      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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