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    pfSense Rewrites Source IP for ICMP Errors Breaking Traceroute

    Scheduled Pinned Locked Moved General pfSense Questions
    icmptraceroutenat
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator
      last edited by

      Sure looks like that is his problem... @Alex-Atkin-UK

      An intelligent man is sometimes forced to be drunk to spend time with his fools
      If you get confused: Listen to the Music Play
      Please don't Chat/PM me for help, unless mod related
      SG-4860 24.11 | Lab VMs 2.8, 24.11

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      • M
        miki725 @Alex Atkin UK
        last edited by

        @Alex-Atkin-UK

        ooooh. I forgot about the limiter:

        d8918570-58cb-43e5-a943-7dfd6d5a99ca-image.png

        can confirm that when I disabled floating rule with the queue, traceroute works as expected inside LAN.

        Thank a lot for linking to that. Now would be curious why a limiter would have that affect.

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        • johnpozJ
          johnpoz LAYER 8 Global Moderator
          last edited by johnpoz

          @miki725 said in pfSense Rewrites Source IP for ICMP Errors Breaking Traceroute:

          Now would be curious why a limiter would have that affect.

          It shouldn't - therefore the bug report ;)

          You should of brought up the limiter, when asked doing anything odd on lan side rules (floating would be considered lan side) hehehe.. I will make sure to always mention floating rules going forward..

          An intelligent man is sometimes forced to be drunk to spend time with his fools
          If you get confused: Listen to the Music Play
          Please don't Chat/PM me for help, unless mod related
          SG-4860 24.11 | Lab VMs 2.8, 24.11

          M 1 Reply Last reply Reply Quote 0
          • M
            miki725 @johnpoz
            last edited by

            @johnpoz said in pfSense Rewrites Source IP for ICMP Errors Breaking Traceroute:

            You should of brought up the limiter, when asked doing anything odd on lan side rules (floating would be considered lan side) hehehe.. I will make sure to always mention floating rules going forward..

            My apologies. Forgot about them. Makes perfect sense that they are as legitimate LAN side rule as any other.

            Thanks everyone for helping even with limited provided information. Really appreciate everyones time and effort. Stay safe!

            A 1 Reply Last reply Reply Quote 0
            • A
              Alex Atkin UK @miki725
              last edited by Alex Atkin UK

              @miki725 I remembered it as I had the same problem.

              As I recall you have to add a Pass floating rule for the WAN interface at the top of the list for echo reply/requests with Quick ticked, so it bypasses the limiter rule.

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              • GertjanG
                Gertjan
                last edited by Gertjan

                @Alex-Atkin-UK : Thanks.

                That were those for :

                1b20b041-6cb8-43d4-8451-16f015d4f5a0-image.png

                ( bottom two rules )

                No "help me" PM's please. Use the forum, the community will thank you.
                Edit : and where are the logs ??

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                • M
                  miki725
                  last edited by

                  Thanks for the suggestion. Didnt even think of bypassing it.

                  Where is a standard place to add limiter rules? Mine is currently is a floating rule. Even with the ICMP bypass rule with Quick above it, traceroute is still impacted:

                  e1a36188-e928-4cd2-8906-4b18b6976bc2-image.png

                  I tried removing the Quick from the limiter rule but that does not seem to help. Only thing which helps is disabling the limiter altogether. Im probably not doing something correctly if this works for you.

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                  • GertjanG
                    Gertjan
                    last edited by

                    Like me, you added floating rules to do something about buffer bloat.

                    These are all my floating rules :

                    bf4bc721-c6d5-485e-9c04-57ccd1ca8c31-image.png

                    You're missing one IPv4 rule : the "direction : IN" rule.
                    You have the "Out" rule, the one with the gateway (WAN_DHCP).

                    I also use IPv6 - so that adds 3 more rules.

                    No "help me" PM's please. Use the forum, the community will thank you.
                    Edit : and where are the logs ??

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                    • B
                      bobbenheim
                      last edited by

                      In your ICMP rule setting direction: out, interface: WAN and change default to your actual gateway in advanced > Gateway
                      should do the job.

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                      • J
                        jamesonp
                        last edited by

                        This got me today. I can confirm the floating rule for ICMP solves the issue.

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