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    Incoming v6 traceroutes are blocked at pfsense box.

    Scheduled Pinned Locked Moved IPv6
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    • M
      Morlok8k
      last edited by

      I have a working native v6 setup (pfsense v2.2.6).  I'm not a stranger to firewall rules with v6.

      I've enabled ICMPv6 (any) to pass through pfsense so i can ping any of my v6 computers on my LAN from the outside internet.

      When i do a traceroute6 from inside my LAN, pfsense is the first hop.  this is normal.

      When i do a traceroute6 from the internet, to a v6 address inside my LAN, the last hop it shows is the hop before my pfsense box.  The pfsense box and the target v6 address dont show up.

      I'm at a loss here.  What am i missing?

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      • M
        Morlok8k
        last edited by

        For future reference, Windows uses ICMP, but Unix based systems default to UDP.

        So unblocking ports 33434 to 33534 over UDP is the answer.

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        • johnpozJ
          johnpoz LAYER 8 Global Moderator
          last edited by

          If I recall the formula is something like

          33434 + (max-ttl * numberofprobes - 1)

          Since each port going to use a different port, where 33434 is the base port.. So for example ding a sniff while doing a traceroute to something behind pfsense I get attached.  So yeah opening up the ports should allow your trace to work when using udp.

          udptraceports.png
          udptraceports.png_thumb
          tracerouteviaudp.png
          tracerouteviaudp.png_thumb

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