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    pfsense and IPv6 default behavior

    Scheduled Pinned Locked Moved IPv6
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator
      last edited by

      @IsaacFL said in pfsense and IPv6 default behavior:

      if you are using Avahi for instance

      Which is not default setup.. So yes if you are adding new services that pfsense to do - then yes you might have to adjust the rules..

      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 2.7.2, 24.11

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      • lohphatL
        lohphat @IsaacFL
        last edited by lohphat

        @IsaacFL This is my original point about pfSense's base config not supporting multicast by default. IPv6 relies on multicast for basic operations (e.g. enumerating the all hosts group) -- why should anyone need to manually enable rules for IPv6 multicast?

        SG-3100 24.11-RELEASE (arm) | Avahi (2.2_6) | ntopng (5.6.0_1) | openvpn-client-export (1.9.5) | pfBlockerNG-devel (3.2.1_20) | System_Patches (2.2.20_1)

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        • johnpozJ
          johnpoz LAYER 8 Global Moderator
          last edited by

          because pfsense doesn't do anything with ipv6 multicast out of the box..

          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 2.7.2, 24.11

          IsaacFLI 1 Reply Last reply Reply Quote 0
          • JeGrJ
            JeGr LAYER 8 Moderator
            last edited by

            And it doesn't have to - per default. We're running an IPv6 enabled dualstacked hosting setup for years now without needing that. Only time I had to actually pass in multicast traffic was for allowing downstream core switch to talk OSPF with the firewall via FRR, and that was necessary for IP4 & IP6. Besides that, nothing comes to mind, that absolutely needs multicast to pass a firewall with IPv6?

            Don't forget to upvote 👍 those who kindly offered their time and brainpower to help you!

            If you're interested, I'm available to discuss details of German-speaking paid support (for companies) if needed.

            lohphatL IsaacFLI 2 Replies Last reply Reply Quote 0
            • lohphatL
              lohphat @JeGr
              last edited by

              @JeGr One of the befits of IPv6 is that it finally fixes multicast to enable realtime media streaming from non-local sources to reduce bandwidth needs consumed by unicast.

              IPTV is one such solution where each channel is it's own multicast channel. http://www.klicktv.co.uk/iptv-multicasting

              SG-3100 24.11-RELEASE (arm) | Avahi (2.2_6) | ntopng (5.6.0_1) | openvpn-client-export (1.9.5) | pfBlockerNG-devel (3.2.1_20) | System_Patches (2.2.20_1)

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              • IsaacFLI
                IsaacFL @JeGr
                last edited by

                @JeGr said in pfsense and IPv6 default behavior:

                And it doesn't have to - per default. We're running an IPv6 enabled dualstacked hosting setup for years now without needing that. Only time I had to actually pass in multicast traffic was for allowing downstream core switch to talk OSPF with the firewall via FRR, and that was necessary for IP4 & IP6. Besides that, nothing comes to mind, that absolutely needs multicast to pass a firewall with IPv6?

                If you turn off ipv4 you will find that some some services may not function correctly without a rule passing multicast into the router. Your dual stack lets it fall back on ipv4.

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                • IsaacFLI
                  IsaacFL @johnpoz
                  last edited by

                  @johnpoz said in pfsense and IPv6 default behavior:

                  because pfsense doesn't do anything with ipv6 multicast out of the box..

                  Not correct. The routing in ipv6 uses multicast and there are some built in rules to pass them in. There are also some that have been missed and are getting blocked that shouldn’t be

                  I know of at least one bug that I submitted that is being fixed in 2.5

                  If you add a pass rule to multicast it fixes it in meantime.

                  lohphatL 1 Reply Last reply Reply Quote 0
                  • lohphatL
                    lohphat @IsaacFL
                    last edited by

                    @IsaacFL This is my point, thanks. There are basic IPv6 functionality which is partially taken care of by default hidden rules and others which need manual intervention. This needs to be cleaned up and or clarified. WAN and LAN segments need to handle link local traffic properly (as an example) for both routing (OSPF broadcasts), ICMP, IGMP, etc. so that basic IPv6 functionality isn't broken due to incomplete/inconsistent/poorly documented defaults.

                    In another pointless rant of mine =), all pfSense settings should have the default setting called out in the setting description. Currently it's very inconsistent.

                    SG-3100 24.11-RELEASE (arm) | Avahi (2.2_6) | ntopng (5.6.0_1) | openvpn-client-export (1.9.5) | pfBlockerNG-devel (3.2.1_20) | System_Patches (2.2.20_1)

                    IsaacFLI 1 Reply Last reply Reply Quote 0
                    • IsaacFLI
                      IsaacFL @lohphat
                      last edited by

                      @lohphat said in pfsense and IPv6 default behavior:

                      @IsaacFL This is my point, thanks. There are basic IPv6 functionality which is partially taken care of by default hidden rules and others which need manual intervention. This needs to be cleaned up and or clarified. WAN and LAN segments need to handle link local traffic properly (as an example) for both routing (OSPF broadcasts), ICMP, IGMP, etc. so that basic IPv6 functionality isn't broken due to incomplete/inconsistent/poorly documented defaults.

                      In another pointless rant of mine =), all pfSense settings should have the default setting called out in the setting description. Currently it's very inconsistent.

                      I think the philosophy of pfSense is that by default everything is rejected. There are some exceptions for some of the internal functions, ie DHCP etc. but for the most part you are expected to explicitly pass via a firewall rule.

                      That way the end user has complete control which means they can also shoot themselves in the foot.

                      lohphatL 1 Reply Last reply Reply Quote 0
                      • lohphatL
                        lohphat @IsaacFL
                        last edited by

                        @IsaacFL I understand that and agree however multicast is intrinsic to IPv6 not optional with IPv4. IPv6 internal consistency of multicast groups replacing broadcast and other functionality means that it should either be enabled fully or a clear, clean setting to enable multimedia multicast. The separation of some things into hidden (supporting host, routing, and service groups) vs. explicit rules (to support media streaming and mDNS) muddles the config process.

                        SG-3100 24.11-RELEASE (arm) | Avahi (2.2_6) | ntopng (5.6.0_1) | openvpn-client-export (1.9.5) | pfBlockerNG-devel (3.2.1_20) | System_Patches (2.2.20_1)

                        JKnottJ 1 Reply Last reply Reply Quote 0
                        • JKnottJ
                          JKnott @lohphat
                          last edited by

                          @lohphat said in pfsense and IPv6 default behavior:

                          I understand that and agree however multicast is intrinsic to IPv6 not optional with IPv4. IPv6 internal consistency of multicast groups replacing broadcast and other functionality means that it should either be enabled fully or a clear, clean setting to enable multimedia multicast.

                          For stuff directly on the LAN, multicast works fine and pfSense is not involved, except for it's own needs. It's only when you go beyond that you have to enable it. This is the same for every just about everything. By default, firewalls block everything coming in.

                          PfSense running on Qotom mini PC
                          i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                          UniFi AC-Lite access point

                          I haven't lost my mind. It's around here...somewhere...

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