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    ["solved"] IGMP w options blocked on lo0 interface, filling the log, can't be silenced

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    • stephenw10S
      stephenw10 Netgate Administrator
      last edited by

      Hmm, interesting. Do you know which build you were running when this was happening?

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        pst @stephenw10
        last edited by

        @stephenw10 it must have been the build prior to 0606: May15 (as it was the previous official build)

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          louis2 @pst
          last edited by

          @pst @stephenw10

          See the blog I did open yesterday!!

          Sevire issues related to IGMP multicast traffic

          I do mention a number of IGMP related issues there!

          And its not the first time I and others complain.

          small peace of my actual log

          cc8f51c0-d63a-4858-a66a-b8f50e10c29e-image.png

          johnpozJ 1 Reply Last reply Reply Quote 0
          • johnpozJ
            johnpoz LAYER 8 Global Moderator @louis2
            last edited by

            @louis2 well that sure looks like just not having ip options set. Create a rule above the default allow that either blocks or allows that traffic and don't log it.

            Or allow ip options on your default allow rule.

            Pfsense more likely than not isn't going to do anything with that traffic anyway.. Not unless you want avahi or pimd running and doing something.

            There should prob be a log setting not to log such noise.. How you turn off logging bogon/rfc and default deny, etc. I haven't looked in 2.8 or the 25.03 better - maybe there is?

            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
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              louis2 @johnpoz
              last edited by louis2

              @johnpoz

              John we had that discussion before. But two things here (also see Sevire issues related to IGMP multicast traffic)

              • pass rules without logging should never ever become block rules with logging
              • and yep despite that an knowing this completely wrong behavoir I did put a rule in front of other rules WITH options set, but even that does not help !!!
              • and apart from that what really happens is completely unclear!

              So .... really nothing is behaving here like it should !!

              205d2959-1d7e-49d7-aad8-9c74b48220b4-image.png

              The title in the bar is not completely valid, but that is not important here. (example copied from my pclan ruleset)

              johnpozJ dennypageD 2 Replies Last reply Reply Quote 0
              • johnpozJ
                johnpoz LAYER 8 Global Moderator @louis2
                last edited by

                @louis2 and what cidrs do you in that alias? I take it you have ip options selected in that rule? since see the gear on it. If it includes the multicast destinations being sent, then I agree that shouldn't log.

                I also agree that blocking on an allow rule especially if any any rule is bit odd, and can be confusing. if the ip options doesn't match the allow rule - then it should fall through and be logged by default deny.

                If have any any, with ip options not allowed - and traffic has ip options the traffic should just not match and fall through.

                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 2.8, 24.11

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                • dennypageD
                  dennypage @louis2
                  last edited by dennypage

                  @louis2 The important thing to keep in mind is that you must have allow IP options set in the rule if you expect it to match a packet with the router alert flag set.

                  Suggest an “Allow” from all rule for IPv4/IPv6 and protocol IGMP on the “Local” interface.

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                  • stephenw10S
                    stephenw10 Netgate Administrator
                    last edited by

                    Yup the change in behaviour there is confusion I agree. It logs on whatever matched the traffic, even if that was pass rule, if IP options are no allowed. This is the correct behaviour now, it was broken for years!

                    See: https://redmine.pfsense.org/issues/15400

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                      louis2 @stephenw10
                      last edited by louis2

                      @stephenw10

                      IMHO the behavoir is fully incorrect! But apart from that I have options set.

                      0a1fdc4f-d979-49d2-8918-923b7cbd027b-image.png

                      Also see part of my rule stack higher up.

                      Note I am running pfSense+ latest beta

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                      • stephenw10S
                        stephenw10 Netgate Administrator
                        last edited by

                        But what's in your MulticastMediaServer alias? Since it's matching the default LAN rule below that.

                        johnpozJ 1 Reply Last reply Reply Quote 0
                        • johnpozJ
                          johnpoz LAYER 8 Global Moderator @stephenw10
                          last edited by

                          @stephenw10 exactly - asked the same question, just because you clicked off ip options, and want this media server(s) to see this traffic doesn't mean that rule actually matched if you put in the servers actual IP address, vs the multicast addresses..

                          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 2.8, 24.11

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                            louis2 @johnpoz
                            last edited by

                            @johnpoz

                            cea17369-128e-4118-8882-f8ccec325f8d-image.png

                            johnpozJ 1 Reply Last reply Reply Quote 0
                            • dennypageD
                              dennypage
                              last edited by dennypage

                              IGMP should be allowed to all.

                              Try this rule on the “Local” interface:

                              4ffeb9b5-1733-472f-938f-e9f84d340e49-image.png

                              db9fc9c3-34c0-44f5-a8e7-c490c02eefe2-image.png

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                              • johnpozJ
                                johnpoz LAYER 8 Global Moderator @louis2
                                last edited by johnpoz

                                @louis2 well that last one is wrong.. its 239.255.255.250

                                so yeah its still going to log that traffic as blocked.

                                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 2.8, 24.11

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                                  louis2 @johnpoz
                                  last edited by louis2

                                  @johnpoz said in ["solved"] IGMP w options blocked on lo0 interface, filling the log, can't be silenced:

                                  239.255.255.250

                                  John you are right, I should have added that address. The problem is that '239.255.255.0' is a range not an address. I do not know the exact usage of 239.255.255.250 however it is a used control address.

                                  However, adding that address does not solve the problem. Below a small part of my actual log

                                  At this particular moment the log shows 244.0.0.1 Note that the shown rule set was already in place when created the picture of the log somewhat higher (showing addresses being filtered)

                                  181bbf34-d0d7-4489-a710-55ace636f94a-image.png

                                  PIMD not yet working properly, could be due to the fact that I did not recompile it yet for FreeBSD15 current, but I am not sure about that.

                                  Next to that I really and fully stick to my vision that rules should do what they say what they do !!!

                                  Not logging pass rules turning in block rules and start logging ....... terrible ...

                                  Rules affecting traffic not selected by that rule .... terrible

                                  I really really can not accepted that as being OK !!

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                                  • stephenw10S
                                    stephenw10 Netgate Administrator
                                    last edited by

                                    You have that rule duplicated on both those interfaces?

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                                      louis2 @stephenw10
                                      last edited by

                                      @stephenw10

                                      No, I had it only enable on the PCLAN, since it is still in an experimental stage. However I see the behavoir on multiple vlans including the PCLAN.

                                      I did add the rule now to the guest vlan and my privileged vlan as well. To keep them equal, not that I expect it to change something.

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                                      • stephenw10S
                                        stephenw10 Netgate Administrator
                                        last edited by

                                        Are you adding it as a floating rule? It doesn't look like that but...

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                                        • dennypageD
                                          dennypage
                                          last edited by

                                          The rule to allow IGMP must come before the default rule you have at the end of the interface. The log entries you posted show that this is not the case.

                                          You can either use a floating rule with quick, or you can use Local. Try what I showed above. You can tighten it up later if you feel the need, but get it working first.

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                                            louis2 @dennypage
                                            last edited by

                                            @dennypage @stephenw10

                                            To answer your questions

                                            Floating
                                            No it am not using floating rules here. In short I only use floating for reasons of security or high performance.

                                            Rule position
                                            There are a couple of things which determs the order I place rules. In short

                                            • security
                                            • performance
                                            • logic

                                            Below the first part of my rule set as related to my PCLAN

                                            3fca7c78-0a26-4ae9-865c-5a6add82f1ce-image.png

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