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    Default Deny rule blocking Broadcasts on the same network?

    Firewalling
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    • A
      alan.t
      last edited by

      Hello,

      Default Deny appears to be blocking .255 on the same network (see attached) ?
      Am I interpreting that correctly ?

      BRgds/Alan

      F2A16F4B-DDF0-4B64-BCDD-841B96354291.jpeg

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      • NogBadTheBadN
        NogBadTheBad
        last edited by

        Yes, no need to pass broadcast traffic past the local interface unless you need to.

        If it’s bugging you when viewing the logs create a rule to block it and not log.

        Andy

        1 x Netgate SG-4860 - 3 x Linksys LGS308P - 1 x Aruba InstantOn AP22

        A 1 Reply Last reply Reply Quote 0
        • A
          alan.t @NogBadTheBad
          last edited by

          @nogbadthebad … mmmm, so this broadcast IS being seen by everything on the .11 network, just being blocked from going to any other network ?

          Alan

          GertjanG 1 Reply Last reply Reply Quote 0
          • GertjanG
            Gertjan @alan.t
            last edited by

            @alan-t said in Default Deny rule blocking Broadcasts on the same network?:

            mmmm, so this broadcast IS being seen by everything on the .11 network

            Because it's a broadcast.
            The device, a.b.11.x send out this special packet that is seen by all other a.b.11.1 to a.b.11.255. That includes the IP a.b.11.y (pfSEnse).
            pfSense has to block it. If not, it would ripple of over all the other networks, local or upstream.
            Internet would die several milliseconds later.

            The final, build-in last firewall rule ( 100000000103) on every interface is a block all rule. Normally, you should 'not log' it's actions.

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

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            • A
              alan.t @Gertjan
              last edited by

              @gertjan … Got it, thank you.

              Cheers/Alan

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

                @alan-t this would normally not be logged by the default deny rule because the default lan rule is any any from the lan net..

                If you have edited the lan rules to be specific and not allowing then default deny would log this by default yes. But even when you have rules to allow this traffic it wouldn't go anywhere because it has no where to go it a directed broadcast for that specific network. Just because pfsense can see it with a rule that allows it doesn't mean it will do anything with.

                Adjust rules so its allowed, or create a specific block rule that doesn't log it, or turn off you logging of the default deny..

                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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