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    ICMPv6, type 2 (Packet Too Big)

    Scheduled Pinned Locked Moved 2.1 Snapshot Feedback and Problems - RETIRED
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    • rcfaR
      rcfa
      last edited by

      From http://test-ipv6.com/

      IPv6 firewalls need to permit ICMPv6, type 2 (Packet Too Big) to work correctly with the public Internet. If you are implementing the IPv6 firewall for your web site, your enterprise, or other organization, please permit this specific ICMPv6 message, even if you by default block other types of ICMP.

      When I try to set up a firewall rule for ICMPv6, I can't find a type "Packet Too Big", is this listed under a different name, or does this need to be added to the pop-up list of ICMP types?

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      • B
        bardelot
        last edited by

        There are a few ICMPv6 types that are required and thus they are allowed by default in pfSense.

        /etc/inc/filter.inc

        # IPv6 ICMP is not auxilary, it is required for operation
        # See man icmp6(4)
        # 1    unreach         Destination unreachable
        # 2    toobig          Packet too big
        # 128  echoreq         Echo service request
        # 129  echorep         Echo service reply
        # 133  routersol       Router solicitation
        # 134  routeradv       Router advertisement
        # 135  neighbrsol      Neighbor solicitation
        # 136  neighbradv      Neighbor advertisement
        pass quick inet6 proto ipv6-icmp from any to any icmp6-type {1,2,135,136} keep state
        
        # Allow only bare essential icmpv6 packets (NS, NA, and RA, echoreq, echorep)
        pass out quick inet6 proto ipv6-icmp from fe80::/10 to fe80::/10 icmp6-type {129,133,134,135,136} keep state
        pass out quick inet6 proto ipv6-icmp from fe80::/10 to ff02::/16 icmp6-type {129,133,134,135,136} keep state
        pass in quick inet6 proto ipv6-icmp from fe80::/10 to fe80::/10 icmp6-type {128,133,134,135,136} keep state
        pass in quick inet6 proto ipv6-icmp from ff02::/16 to fe80::/10 icmp6-type {128,133,134,135,136} keep state
        pass in quick inet6 proto ipv6-icmp from fe80::/10 to ff02::/16 icmp6-type {128,133,134,135,136} keep state
        
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