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    Setting MTU seem to not take effect

    Scheduled Pinned Locked Moved webGUI
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    • P
      pirron
      last edited by

      I don't know why in my Diagnostics/Routes MTU setting is shown as 1500 even tho I specified id in Interfaces/WAN to 1496  ???
      I'm using pfsense 1.2.2
      Screen shots on the bottom.
      WAN.jpg
      WAN.jpg_thumb
      Routes.jpg
      Routes.jpg_thumb

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      • jimpJ
        jimp Rebel Alliance Developer Netgate
        last edited by

        The MTU is set via MSS Clamping and will not show up as an altered MTU on the Routes page.

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        • P
          pirron
          last edited by

          Thank you for the quick answare sir.

          So lets say I use MSS - would I need to change MTU on my routers sitting behind pfsense to 1492 or the clamping on pfsense would take care of the whole packet management in the network?

          Is MSS Clamping tool accesssible from the WebGUI?

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          • jimpJ
            jimp Rebel Alliance Developer Netgate
            last edited by

            You shouldn't need to change anything sitting behind pfSense, it should be handled automatically.

            You set the MSS clamping value by setting the MTU, there is nothing else to set for it right now. There may be some other options in 2.0 though.

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            • P
              pirron
              last edited by

              So … to gain full clerness on this: setting the MTU which is effectively MSS Clamping value in WAN tab as I did to 1492 will in effect result in having MTU of 1492 which will not be shown in Routes tab as 1492 for all devices behind pfsense? In other words the value I've set in  MTU field under WAN tab did what I wanted to achieve?

              Just simple "yes" or "no" would be more than satisfactory.

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              • jimpJ
                jimp Rebel Alliance Developer Netgate
                last edited by

                Yes.

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                • P
                  pirron
                  last edited by

                  ;D <- I just couldn't resist!

                  Thank you!

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