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    PfSense not replying to UDP traceroute on WAN

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

      Yup same rule here..

      wantraceroute.png
      wantraceroute.png_thumb

      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 25.07.1 | Lab VMs 2.8, 25.07.1

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      • DerelictD Offline
        Derelict LAYER 8 Netgate
        last edited by

        that's a lot of NTP traffic…. :)

        Chattanooga, Tennessee, USA
        A comprehensive network diagram is worth 10,000 words and 15 conference calls.
        DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
        Do Not Chat For Help! NO_WAN_EGRESS(TM)

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        • johnpozJ Offline
          johnpoz LAYER 8 Global Moderator
          last edited by

          Yeah have a stratum 1 in the pool..

          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 25.07.1 | Lab VMs 2.8, 25.07.1

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          • T Offline
            travisbrackett
            last edited by

            That did the trick! Thanks!

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            • T Offline
              travisbrackett
              last edited by

              One weird thing I'm seeing is with Windows tracert which uses ICMP, pfSense sends a TTL expired reply when the request TTL is < 6, so I get a weird result where my pfSense firewall shows up 5 times. I don't want to reject ICMP packets, and I don't see a way to configure the TTL threshold. Anyone know of a remedy?

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              • DerelictD Offline
                Derelict LAYER 8 Netgate
                last edited by

                I would need to see a packet capture of that.

                Chattanooga, Tennessee, USA
                A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                • T Offline
                  travisbrackett
                  last edited by

                  Here you go. I've anonymized the pcap so 1.1.1.1 is the host running the traceroute, and 2.2.2.2 is my pfSense firewall. Looks like I was wrong and it stops sending a TTL expired, and starts replying, when the TTL is greater than 4.

                  Edit: Oops, there's a 1:1 NAT and the replies are probably the routers in between and the host the packets are being NATted to.

                  Edit: Packet capture on the LAN interface confirms this theory.

                  icmptraceroute_anonymized.pcap

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                  • DerelictD Offline
                    Derelict LAYER 8 Netgate
                    last edited by

                    OK you're kind of all over the place. You state that pfSense responds in the negative with a TTL > 4. What, exactly am I looking for?

                    What interface was that pcap taken on?

                    Anonymizing MAC addresses? Really? I can't help you.

                    Chattanooga, Tennessee, USA
                    A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                    DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                    Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                    • johnpozJ Offline
                      johnpoz LAYER 8 Global Moderator
                      last edited by

                      "One weird thing I'm seeing is with Windows tracert which uses ICMP, pfSense sends a TTL expired reply when the request TTL is < 6"

                      From where to where?

                      I trace through pfsense to internet all the time, never seen such a thing..

                      singlepfsenseintrace.png
                      singlepfsenseintrace.png_thumb

                      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 25.07.1 | Lab VMs 2.8, 25.07.1

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                      • A Offline
                        axsense2
                        last edited by

                        What was the resolution? I am having the same problem as in topic. Tracing PFSense from outside PFSense seems that it is not recognizing traces at all. Ping works fine. It can't be true that PFSense does not work with Traceroute in UDP mode... can it?

                        Ax.

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                        • johnpozJ Offline
                          johnpoz LAYER 8 Global Moderator
                          last edited by

                          Ah screenshot is missing - prob got lost when they updated the forum... You juts need to set a reject rule on your wan for the udp ports. When get back from lunch can post up a screenshot.

                          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 25.07.1 | Lab VMs 2.8, 25.07.1

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                          • A Offline
                            axsense2
                            last edited by

                            Got it... I think. I created Rejected rule for UDP between ports 33434 and 33634. It actually resolves the issue.

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                            • johnpozJ Offline
                              johnpoz LAYER 8 Global Moderator
                              last edited by johnpoz

                              yup... that is all you need to do.

                              edit: for the next guy that finds this thread... I will post up screenshot of the rule
                              tracerouterule.png

                              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 25.07.1 | Lab VMs 2.8, 25.07.1

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