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    IPSect Site to Site (Slow Upload) - (Fast Download) issue

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    • A
      AMD_infinium05
      last edited by

      RESOLVED!!
      I have set both ends to MSS Clamping 1300 and that solved the issue.
      I can now upload data to Qnap at full speed 80-90Mbps.

      Wrap up thoughts?

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      • P
        P3R
        last edited by

        Wouldn't it be better to fix what's preventing MTU discovery to work properly (your ICMP filtering perhaps)?

        I've never needed MSS Clamping.

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        • A
          AMD_infinium05 @P3R
          last edited by

          @p3r ICMP filtering?

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          • P
            P3R
            last edited by

            As far as I know MSS Clamping is a workaround to avoid MTU discovery problems. I assumed that you have some filtering in the source-destination path (ICMP was my first thought) that prevent MTU discovery.

            Since throughtput was assymetric, I expected it to be fairly easy to find what was different and causing the issue at one end.

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