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    IGMP IPV4 endless log-messages / rules not working :(

    Scheduled Pinned Locked Moved Firewalling
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    • dennypageD Offline
      dennypage @louis2
      last edited by

      @louis2 said in IGMP IPV4 endless log-messages / rules not working :(:

      IP-options is necessary for a match, than the rule without IP-options, should simply not match should not do any thing !!

      To be clear, IP options are not matchable like protocols, addresses, ports, etc.

      L 1 Reply Last reply Reply Quote 0
      • L Offline
        louis2 @dennypage
        last edited by

        @dennypage

        I think I fixed it. The following way:

        1. I did add as first rule for the vlan:
          4e05d9d7-b8e2-449e-9001-96971c4f14bd-image.png

        2. I did reset the states via Diagnostics / States / Rest States

        Just defining the rule, was not enough !!!

        dennypageD 1 Reply Last reply Reply Quote 0
        • dennypageD Offline
          dennypage @louis2
          last edited by

          @louis2 Glad you got it working. Thank you for letting me know that you had to perform Reset States. That may help others.

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          • GertjanG Offline
            Gertjan @louis2
            last edited by

            @louis2 said in IGMP IPV4 endless log-messages / rules not working :(:

            So I would never ever define a rule like "every thing outgoing allowed.
            Next to that the rules allow all subsets to freely communicate with each other. No way !! Never !!

            I fully agree with that.
            I've kept the default Netgate LAN firewall rules because I have the luxury of totally trusting all my LAN devices, I don't need to block something from going outside.
            Beyond the devices, I can also trust the users that uses these devices. I'm lucky, probably.

            Closing all destination ports, leaving open only port 53,80,443,110,143,995,992, 993, 143 doesn't give me more security, as 99% of all threads are downloaded by users over 443 (a web browser using https) or by mail, for example IMAP SSL, port 993, a mail client.

            My LAN is my trusted network, and they could access to my other, less trusted networks, like a captive portal, or my server network. These networks can not access my trusted LAN.
            My non trusted networks have devices I need to admin, like access points etc. I can access these from my LAN.

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

            dennypageD 1 Reply Last reply Reply Quote 0
            • dennypageD Offline
              dennypage @Gertjan
              last edited by

              @Gertjan In this case, it's a bit more than just passing ports. Allowing IP Options on a pass all rule opens your firewall to these options as well. IMO, you want to be very specific in the circumstance that you allow IP options.

              I would have a preference to silently dropping all packets with IP options, including IGMP, rather than allowing all IP packets with options.

              GertjanG luckman212L 2 Replies Last reply Reply Quote 0
              • GertjanG Offline
                Gertjan @dennypage
                last edited by

                @dennypage said in IGMP IPV4 endless log-messages / rules not working :(:

                you want to be very specific in the circumstance that you allow IP options.

                I wanted to clean my logs. I've chosen the fast way out - not necessarily the best one.

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

                1 Reply Last reply Reply Quote 0
                • luckman212L Offline
                  luckman212 LAYER 8 @dennypage
                  last edited by luckman212

                  Hello from 2025.

                  On my 6100 running 25.07, I'm noticing these IGMP packets getting blocked (they were probably there all along but since I'm troubleshooting multicast issues I happened to be digging around and saw them)

                  I haven't collected packet dumps of this traffic yet, but based on the LAN IPs of the 2 hosts below, I identify them as my main Mac workstation and a Windows 11 VM, so it's not platform-specific.

                  3ccfcce2-6eab-44c3-8cd2-03e26a108b2e-image.png

                  806dd394-6c1e-4be8-a55d-057d6df6a55e-image.png

                  That "inet access" rule is the very bottom of my ruleset on the LAN interface, and looks like this

                  c1e85bdc-cd2a-4992-8b6b-6dd5c2e45554-image.png

                  What's the best course of action here?

                  • Make a separate rule just above it that allows ip-options just for protocol IGMP?
                  • Just ignore them?
                  • Something else?

                  Do I need IGMP Proxy enabled for any reason?

                  8e443c13-b56f-4346-bc83-5a1e42b1a433-image.png

                  edit: I decided to go with a rule to pass IGMP on the LAN for now. It's matching...

                  5222e456-08e0-4902-a037-90908710eb88-image.png

                  444a5809-2836-4362-8112-ffaf610785cb-image.png

                  Thinking about this, I'm not sure that this actually does anything other than tidy the logs. Once the IGMP packet hits my pfSense, I don't think it "goes" anywhere useful.

                  dennypageD 1 Reply Last reply Reply Quote 0
                  • dennypageD Offline
                    dennypage @luckman212
                    last edited by

                    @luckman212 I have this in Firewall / Local / Rules:
                    Screenshot 2025-08-18 at 14.25.48.png

                    Screenshot 2025-08-18 at 14.28.26.png

                    There really isn't much reason to suppress IGMP packets in the local network.

                    johnpozJ luckman212L 2 Replies Last reply Reply Quote 0
                    • johnpozJ Offline
                      johnpoz LAYER 8 Global Moderator @dennypage
                      last edited by

                      @dennypage while I agree - pfsense isn't going to do anything with it.

                      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

                      dennypageD 1 Reply Last reply Reply Quote 0
                      • dennypageD Offline
                        dennypage @johnpoz
                        last edited by

                        @johnpoz said in IGMP IPV4 endless log-messages / rules not working :(:

                        while I agree - pfsense isn't going to do anything with it.

                        Depends upon what packages you are using I guess. From a switch POV, IGMP is pertinent for Avahi, mDNS-Bridge, mcast-bridge (not yet released), IGMP proxy and pimd. Perhaps others that I am not aware of.

                        IGMP is a goodness that prevents unnecessary multicast packet flooding. In my view, it should always be enabled if available.

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                        • luckman212L Offline
                          luckman212 LAYER 8 @dennypage
                          last edited by

                          "Firewall / Local / Rules"

                          I assume Local is an interface group you created? Good idea. I just changed mine:

                          edc3fcd8-71ab-4c4f-961a-aebda8687d18-image.png

                          I read the Wikipedia article on IGMP, and according to my interpretation, it's an IPv4-only protocol. So there shouldn't be a need to allow IPv6 there (saw v4+v6 in your screenshot)

                          In any case, I agree with @johnpoz that this is tilting at windmills.

                          dennypageD 1 Reply Last reply Reply Quote 0
                          • dennypageD Offline
                            dennypage @luckman212
                            last edited by

                            @luckman212 said in IGMP IPV4 endless log-messages / rules not working :(:

                            I assume Local is an interface group you created?

                            Yes, sorry I didn't point that out. Yes, I use a "Local" group for controlling a bunch of stuff such as ICMP, IGMP, DNS, NTP, etc.

                            Btw, yes you are correct IGMP is only used for IPv4. It's a habit I guess (and a poor one at that) that I casually choose IPv4/IPv6. For IPv6, ICMP/MLD is what is actually used, but I believe a rule for this is not necessary because the MLD packets do not have the router alert bit set (at least on my Cisco switches, YMMV).

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