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    how to stop logging blocked LAN IGMP?

    Scheduled Pinned Locked Moved General pfSense Questions
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    • J
      JeremyJ 0 @dennypage
      last edited by

      @dennypage good point.

      I changed the 'silent block' to a 'silent pass', but it behaved the same as the default pass rule: it blocks IGMP (even though the rule is explicitly a pass) and logs each instance (even though the rule is set to not log).

      It appears that the new release has some kind of special code path for this that defies normal handling.

      So, back to blocking it. I don't have the skills or energy to turn off the IGMP sources on my LAN and I don't want those log entries.

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

        @JeremyJ-0 You have to have IP options enabled in the pass rule.

        Edit: Mine is a floating rule, but here's what it looks like:


        Screenshot 2024-05-02 at 08.17.21.png
        Screenshot 2024-05-02 at 08.17.36.png
        Screenshot 2024-05-02 at 08.17.49.png

        J 1 Reply Last reply Reply Quote 0
        • J
          JeremyJ 0 @dennypage
          last edited by

          @dennypage actually tried it both ways. same result. it's silent as a block rule, and noisy as a pass rule.

          Screenshot 2024-05-02 at 11.19.27 AM.png

          Screenshot 2024-05-02 at 11.16.22 AM.png

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

            @JeremyJ-0 Source should be any rather than LAN subnets.

            I edited my post above and put in my floating rule which handles IGMP.

            J 1 Reply Last reply Reply Quote 0
            • J
              JeremyJ 0 @dennypage
              last edited by

              @dennypage did my level best to match your rule: made mine floating, checked 'quick', changed direction to 'in'. It's not exact because I need it to apply to multiple sources where yours is specific to one so left source as 'all'.

              Still getting deny entries in the log.

              dennypageD 2 Replies Last reply Reply Quote 0
              • dennypageD
                dennypage @JeremyJ 0
                last edited by

                @JeremyJ-0 You do not need to restrict it. You can, and should, use "any" unless you have a good reason not to.

                Do exactly this:

                Screenshot 2024-05-02 at 08.49.56.png

                Screenshot 2024-05-02 at 08.50.08.png

                Make sure the rule is above your default allow.

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

                  @JeremyJ-0 Just to be sure, you are doing Apply Changes after modifying the rules, yes?

                  Btw, in Redmine 15415 there is a small patch that you can use to enhance the hover tooltip in the firewall log. It will show "block/ip-option" in the tooltip if the packet was blocked due to the presence of IP options.

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

                    @dennypage said in how to stop logging blocked LAN IGMP?:

                    It will show "block/ip-option" in the tooltip if the packet was blocked due to the presence of IP options.

                    Isn't that kind of obvious when the rule name is pass, but its a block and the protocol is IGMP ;)

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                    J 1 Reply Last reply Reply Quote 1
                    • J
                      JeremyJ 0 @johnpoz
                      last edited by

                      Yes, I 'apply changes' and wait for the filter to reload.

                      Update: after the last round of changes (moving rule to floating etc.) things were worse: the silent block rule was logging the blocked packets too.

                      I rebooted. The excess logging stopped.

                      Is there some part of the firewall that reads the rules on startup and does not re-read on a filter reload?

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

                        @JeremyJ-0 said in how to stop logging blocked LAN IGMP?:

                        Is there some part of the firewall that reads the rules on startup and does not re-read on a filter reload?

                        Not that I am aware of.

                        The reload of rules failing would explain your results however.

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