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    Ntop showing 54% bad packets on internet interface

    Scheduled Pinned Locked Moved General pfSense Questions
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    • F
      familyguy
      last edited by

      I'm assuming this is some sort of anomaly.  Anyone else using ntop and seeing an inordinate number of packets with bad checksums on their internal interface?  Isn't that usually a sign of a bad cable or bad network card/port?  Or is this some strange dynamic between freebsd and ntop?

      Scratching my head….

      Best,

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      • K
        ktims
        last edited by

        Could be caused by checksum offload, I believe.

        Edit: IOW checksum offload would make the checksum calculation invisible to ntop, it'd see all outgoing traffic as having a bad checksum. Not that you should disable checksum offload and that will fix the problem (though it probably will appear to).

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        • jimpJ
          jimp Rebel Alliance Developer Netgate
          last edited by

          Others have reported the same thing, where ntop reports just over 50% of traffic as bad.

          I believe it did have something to do with checksum offloading or NAT causing some checksums to appear bad.

          Either way it seems to be purely cosmetic.

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