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    Packets not hitting rule they should

    Scheduled Pinned Locked Moved Firewalling
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator
      last edited by

      Yeah been working with firewall since the first packet filters ;)

      Juniper, Checkpoint, Cisco ASA and Pix, etc.  Name it and prob have had hands it as some time or the other.

      How many vlans you have… 1000?  Then you might have a point.  10 or 20 or so then no its easier to work with the interfaces..

      Like said going to agree to disagree here ;)  But your log is showing out of state hits.. That traffic would never be passed be it you created a special log rule or not.. default log would log those as well if you left that on, etc.

      From multiple years experience here on the boards.  It's either something like a cell phone moving from cell to wifi trying to use the same session vs creating a new one.  Or OLD sessions, etc.. But normally is an asymmetrical problem.  You mention lots of vlans - any of those "downstream" at a different router?  And not via a transit.

      Without a diagram not going to be able to help you find your problem.

      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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      • S
        SteveFW
        last edited by

        Hello John,

        I solved my problem by adding a VLAN interface on my Mac in VLAN200 (where the other folks are) and route VLAN30 through the VLAN200 interface on the pfSense pair.
        My Mac now has a normal Interface in the server VLAN1 and a VLAN interface in VLAN200. Default gateway is the pfSense Interface in the server VLAN1 and I told my Mac to route 192.168.30.0/24 to the VLAN200 interface of the pfSense CARP.
        I added the needed rules and viola, no more funky chicken. Outlook sessions are kept open and it works like a charm.

        Still, my curiosity of "WFT is going on" (or "was going on") remains. So as a diagram, picture this:  the Firewall in the middle and three legs, one in "server" VLAN1 (where my Mac is and the Exchange server is). The other in the client VLAN200. The third leg is VLAN30 (DMZ) where the Load-Balancer has it's public facing interfaces and the VIP 192.168.30.119.
        Very simple. The other 13 VLAN's + WAN are not relevant.

        I ran Wireshark on my Mac and on the Exchange server. They are(were) not exchanging packets in any way. My Mac (before adding it to VLAN200 as a second interface) only ever sends 443 traffic to the VIP in VLAN30.

        What is interesting is, in the old situation before my Mac got a leg in VLAN200, is that when I closed Outlook, and verified that it really was gone and netstat shows everything gone too, up to a minute later, I still get "FIN" and "ACK" dropped packets (like in the screenshot above). So packets are swirling around for a while, belonging to nothing and thus not to any valid state. And get dropped.

        What is really weird is that my old CheckPoint gives me no trouble and shows no out of state stuff. If I power off the pfSense pair, clear ARP tables, power on the CheckPoint box, everything works fine (i temporarily removed the VLAN200 Interface before putting the CheckPoint back into service). When I start using the pfSense pair again, the problem is back and Outlook connections start dying when VLAN1 is used to communicate.

        Again I don't have an issue at the moment due to the "add vlan200 to Mac and route VLAN30 over it trick" but i'm just curious why pfSense sees packets out of state.

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        • johnpozJ
          johnpoz LAYER 8 Global Moderator
          last edited by

          " i'm just curious why pfSense sees packets out of state."

          Because it sees a packet it has no state for ;)  That is not a SYN..

          Placing a box on more than 1 vlan normally leads to the kind of shit your seeing.  Why would your MAC need an interface in more than 1 vlan??

          That is not a picture that is words! – Actual picture worth 1000+ of those...

          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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          • S
            SteveFW
            last edited by

            All right all right here is ya pictja.

            Why does everything work hunky dory when I route over VLAN200 (dotted green line which is my workaround) and not over VLAN1 (blue) which has my Default Gateway.
            The Default Gateway for all VLAN's are the .254 IP's in the respective networks where something.254 is always the central firewall.

            I'll need to run TCPdump on the PFsense to find out the root cause. Wiresharks on any clients and servers show nothing strange.

            Diagram.png
            Diagram.png_thumb

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            • johnpozJ
              johnpoz LAYER 8 Global Moderator
              last edited by

              Well that sort of setup is RIPE for asymmetrical traffic..

              If your mac sends to its gateway to get to .200.x and .200.x answers back direct on their shared network.

              Again what is the POINT of mac having a leg in the .200.x network?  Is it just for storage?

              And defeats the whole point of a firewall..

              Where is the switch that connects all of these different networks to pfsense? Quite possible you have vlans that are not actually isolated can cause problems as well when you multi home a box like your mac.

              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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              • S
                SteveFW
                last edited by

                No no no having an interface in VLAN200 is a new thing, as it solves the problem of wierd packet drops. I decribed it above. I solely route VLAN30 over the .200.254 interface now to make my Outlook work. It's a stupid work around but if it's stupid but it works, it's not stupid…

                Forget about the second interface for now. Ignoring the green dotted line completely brings us to how it was when I started my thread. As you can see, it's a clean setup and wiresharking proves no packets being (attempted) via funny ways. My Mac REALLY only talks to the .119 VIP in VLAN30. Both ends show clean traffic-flows and nothing flying in some wierd direction. And again, the CheckPoint, which is picky as hell when it comes to assym.routing, causes no trouble.

                So forget about that second interface on my Mac. Go back to the beginning. My question would be: How, besides having packet-dumping proof of clean traffic flow, can I start understanding why pfSense thinks there are packets out of state where as the CheckPoint, configured in fundamentally exactly the same way, sees no issues and doesn't drop packets.
                What is pfSense thinking? I think it has a different opinion as to "what a state is" compared to checkpoint. I just want to understand why it has this opinion about these packets.
                Outlook sessions always start out ok after the program is started. Then, within 10 to 15 seconds, the connection to the VIP start to die and the logs start showing these dropped packets. When I press the "Fetch mail now" button in Outlook, it sets up a new connection, fetches mail, then 10 to 15 seconds later, this new connection dies again.

                This does not happen when I create a second Interface in VLAN200 and forcefully route Outlook's connection to the VIP 192.168.30.119 over the 192.168.200.254 interface instead of the default gateway on 192.168.10.254
                The Load-balancer Pair that the VIP runs on, has a default gateway of 192.168.30.254

                Netstat -rn output:

                imac:~ steve$ netstat -rn -f inet
                Routing tables

                Internet:
                Destination        Gateway            Flags        Refs      Use  Netif Expire
                default            192.168.10.254    UGSc          53        0    en0
                127                127.0.0.1          UCS            0        0    lo0
                127.0.0.1          127.0.0.1          UH            32  299344    lo0
                169.254            link#5            UCS            0        0    en0
                169.254            link#10            UCSI            0        0  vlan0
                192.168.10        link#5            UCS            10        0    en0
                192.168.10.19      0:50:56:a8:40:1e  UHLWI          0    13238    en0  1160
                192.168.10.24      0:11:32:33:c6:c3  UHLWIi          5    2971    en0  1044
                192.168.10.51/32  link#5            UCS            0        0    en0
                192.168.10.52      0:25:90:d8:2:8e    UHLWIi          9      812    en0  1081
                192.168.10.101    0:50:56:a8:54:9e  UHLWIi          1    9361    en0    563
                192.168.10.148    0:50:56:a8:54:a2  UHLWI          0        0    en0    898
                192.168.10.204    0:50:56:ae:46:a6  UHLWIi          1    10699    en0  1192
                192.168.10.237    0:50:56:ff:ea:3c  UHLWIi          2        0    en0    758
                192.168.10.245    link#5            UHLWIi          4        0    en0
                192.168.10.249    f4:ea:67:89:32:7a  UHLWI          0        0    en0  1106
                192.168.10.254/32  link#5            UCS            1        0    en0
                192.168.10.254    0:0:5e:0:1:78      UHLWIir        7        0    en0  1166
                192.168.200        link#10            UCS            3        0  vlan0
                192.168.200.234    2.11.32.20.c3.9b  UHLWIi          3 14065744  vlan0    157
                192.168.200.235/32 link#10            UCS            0        0  vlan0
                192.168.200.254    0.0.5e.0.1.7c      UHLWIi          2        0  vlan0  1163
                224.0.0/4          link#5            UmCS            2        0    en0
                224.0.0/4          link#10            UmCSI          1        0  vlan0
                224.0.0.251        1:0:5e:0:0:fb      UHmLWI          0        0    en0
                239.255.255.250    1:0:5e:7f:ff:fa    UHmLWI          0      357    en0
                239.255.255.250    1:0:5e:7f:ff:fa    UHmLWI          0      357  vlan0
                255.255.255.255/32 link#5            UCS            0        0    en0
                255.255.255.255/32 link#10            UCSI            0        0  vlan0
                imac:~ steve$

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                • johnpozJ
                  johnpoz LAYER 8 Global Moderator
                  last edited by

                  And how do you have these networks isolated at layer 2?  That is the most important part which you have left out of your drawing.

                  Why does it show vlan0?  Vs vlan200?

                  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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                  • S
                    SteveFW
                    last edited by

                    "And how do you have these networks isolated at layer 2?  That is the most important part which you have left out of your drawing."
                    Swtiches and VMware doing VLAN's.

                    "Why does it show vlan0?  Vs vlan200?"
                    I assume that is what MacOS calls the first VLAN Interface that one creates. The second would be called "vlan1". The naming is independent of the VLAN ID used or the Name given to it in the GUI (in the GUI it's called "Vlan200").

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                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator
                      last edited by

                      "Swtiches and VMware doing VLAN'"

                      This is where you could have a problem..

                      Keep in mind your traffic might not be asymmetrical.. It could just be some bad acting application… Or if your running multiple layer 3 over the same layer 2 (ie not proper layer 2 isolation) you could get weird stuff happening.

                      Your idea of sniffing at pfsense makes sense to try and determine why pfsense is seeing out of state traffic.

                      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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                      • S
                        SteveFW
                        last edited by

                        "Or if your running multiple layer 3 over the same layer 2"

                        Both pfSense VM's have three vmxnet3 interfaces:
                        1 x WAN (VLAN1000) connected to a classical dvSwitch Portgroup that only has the relevant VLAN.
                        1 x SYNC (VLAN61) connected to a classical dvSwitch Portgroup that only has the relevant VLAN.
                        1 x TRUNK which is a VLAN-Trunk on the VMware level with only the 17 VLAN's configured that I need to present to this particular firewall-pair. VLAN200, VLAN30 and VLAN1 are amongst those that go "through" it.

                        As discussed all VLAN's go through this Trunk Portgroup, and VLAN30 and 200 don't bite, I cannot think of a reason why the combination VLAN1 and VLAN200 should.

                        Attached a screenshot of one of the two pfSense nodes. Both are identical.

                        ![pfSense vmNIC Config.png](/public/imported_attachments/1/pfSense vmNIC Config.png)
                        ![pfSense vmNIC Config.png_thumb](/public/imported_attachments/1/pfSense vmNIC Config.png_thumb)

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