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    Trying to understand the firewall rules

    Scheduled Pinned Locked Moved Firewalling
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    • V Offline
      viragomann
      last edited by

      That packets are out of state: https://doc.pfsense.org/index.php/Why_do_my_logs_show_%22blocked%22_for_traffic_from_a_legitimate_connection

      Maybe you have an asymmetric routing issue.
      https://doc.pfsense.org/index.php/Asymmetric_Routing_and_Firewall_Rules

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      • C Offline
        coxhaus
        last edited by

        I have a layer3 switch routing to pfsense with a 24 bit mask but I have no connections other than pfsense and a Cisco L3 SG300-28 switch.  This has been in place since 2.2.6 with no changes.

        Is this an issue with 2.3?  How am I going to fix this?

        Update
        I checked the static routing filtering option under Advanced Firewall/NAT.  I will watch and see.

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        • C Offline
          coxhaus
          last edited by

          Nope still seeing the same thing.

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          • H Offline
            Harvy66
            last edited by

            @coxhaus:

            Nope still seeing the same thing.

            What's the problem? PFSense is a stateful firewall and enforces proper TCP connections. If some of your devices are not following proper TCP protocol, PFSense blocks those packets.

            Your images are full of dropped FIN and RST packets, where are used to signal to tear down a connection. The problem is the connection has already been torn down and no longer exists. Sending out of state packets to non-existent states are by definition invalid packets, under all circumstances.

            If you can show the PFSense is improperly blocking new states or blocking  valid packets for existing states, then you have something to show, but blocking invalid packets for non-states is a feature.

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            • C Offline
              cmb
              last edited by

              The 993 traffic (IMAP/S to Google) is probably phones that try to retain their mail connection after switching networks (which can't work, but some phones apparently aren't smart enough to figure out their TCP sessions don't remain valid if they change IPs). The HTTPS shown is to Facebook, which might be the same. Usually that's phones switching from cell network to wifi.

              If those are all cell phones, or other devices that switch IPs, that's expected.

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              • johnpozJ Offline
                johnpoz LAYER 8 Global Moderator
                last edited by

                ^ exactly if you do not want to log out of state packets then turn off default blocking.. And just create a block rule at the bottom of the interface that blocks but only logs with syn flag.  Your default block rule is still there but not logging.  And you can just log stuff that has syn set so you don't see the blocked out of state packets.

                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

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                • C Offline
                  coxhaus
                  last edited by

                  I think you are correct about one of the devices is my wife's iPhone 6s which has cell service also.  The other device 192.168.0.77 is her iPad which does not have cell service. It only runs using wireless in my house. My wife is complaining about slow email.  This and the Hulu TV issue are the 2 issues I am trying to resolve which  were not issues under 2.2.6

                  My wife is complaining about her Apple devices not checking email very fast even if she stands right next to the wireless device.  It seems real slow to respond.  I run 3 Cisco wireless APs using single point setup.  This system has not changed since before 2.2.6.  The wireless APs all run from my Cisco layer3 switch which has not changed either.  So all the traffic is routed LAN traffic.

                  I have included my gateway does this look correct?  I was wondering about the monitor IP on the LAN side?

                  Capture5.PNG
                  Capture5.PNG_thumb

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                  • C Offline
                    coxhaus
                    last edited by

                    The email problem is solved.  My wife had her iPhone in the guest network and her iPad in the main LAN.  There is a ACL blocking the 2 VLANs.  Both are now back in the same VLAN where they should be.

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                    • C Offline
                      coxhaus
                      last edited by

                      I just noticed I woke up my Windows 10 machine and I see this in the firewall log.  Is this normal to block all this out bound traffic?  The list is longer than a screen full so I only captured one screen. This is all routed traffic from my Cisco layer3 switch.

                      Capture.PNG
                      Capture.PNG_thumb

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                      • C Offline
                        cmb
                        last edited by

                        Yes, when you brought it out of sleep it tried to disconnect the connections it had open at the time it went to sleep (mostly, those are the FIN ACKs, others it was still trying to use), but those were already timed out. Not a SYN, and not part of an established TCP connection means blocked.

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                        • C Offline
                          coxhaus
                          last edited by

                          At the same time this was happening with my workstation Hulu had time outs streaming.  Hulu had been streaming for over an hour without any time outs but I came home and fired my laptop up from sleep and Hulu started having time out problems.

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                          • C Offline
                            cmb
                            last edited by

                            Assuming all those blocks are from the laptop's IP, none from the system running Hulu, that's unrelated.

                            That would either be a coincidence, or maybe bringing the laptop on the network does something that impacts the device that's streaming Hulu. Something like creating an IP conflict, or extremely heavy bandwidth usage by the laptop, are the first couple things that come to mind.

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                            • C Offline
                              coxhaus
                              last edited by

                              Maybe a coincidence.  I have a TWC 300 meg connection and all this hardware was in place with 2.2.6.  No time outs with 2.2.6.

                              No conflict with IP addresses as the TV streaming Hulu is in a different VLAN.

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                              • C Offline
                                cmb
                                last edited by

                                With a connection that fast, you almost certainly wouldn't be hitting it hard enough to cause issues for other devices. Probably the only case where that'd happen is if the laptop had malware on it that blasted a bunch of traffic out, maxing out your upload with a flood of traffic, which will significantly impact your downstream performance. That doesn't sound likely either. It being on a different VLAN eliminates all the local network specific possibilities.

                                I'd packet capture on the VLAN where the TV resides, filtered on its IP, and see what the traffic looks like when it stalls.

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                                • C Offline
                                  coxhaus
                                  last edited by

                                  I have a packet capture with Hulu streaming freezing and starting over.  I can't add it as an attachment.  What do we want to do with it?

                                  pfsense.txt

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                                  • johnpozJ Offline
                                    johnpoz LAYER 8 Global Moderator
                                    last edited by

                                    yeah that is pretty useless.  Can you not just attach the actual capture or upload it somewhere we can grab 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

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                                    • C Offline
                                      coxhaus
                                      last edited by

                                      I zipped it.  This is a capture of the LAN interface when Hulu freezes and replays.

                                      packetcapture.zip

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                                      • johnpozJ Offline
                                        johnpoz LAYER 8 Global Moderator
                                        last edited by

                                        There is nothing wrong in that short capture of whole .6 seconds..  What exactly are we suppose to see in such a small sniff..  I see 1 dup ack.. Did you forget to change it from the default 100 packets?  Which is what that sniff 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
                                        SG-4860 25.07.1 | Lab VMs 2.8, 25.07.1

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                                        • C Offline
                                          coxhaus
                                          last edited by

                                          OK. I will enter 0 for packet count.  Anything else I need to change?  I will run it again.

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                                          • C Offline
                                            coxhaus
                                            last edited by

                                            I have another capture but the file is too large to attach.  I get an error from your system.

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