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    Having LAN issues related to a new switch

    Scheduled Pinned Locked Moved General pfSense Questions
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    • H
      HansSolo @KOM
      last edited by HansSolo

      @KOM

      Taken directly from the logs a few seconds ago.....

      May 14 19:03:01 LAN LAN allow (1557864558) 192.168.0.103:53837 192.168.0.2:3406 TCP:S

      As I said, traffic from LAN-Interface to any LAN-Device and vice-versa IS logged.
      So, I should at least see the PC going to the Interface.....but for these connections I do not.
      That's what's got me puzzled.

      So let's say I try to connect to 192.168.0.2 from 192.168.0.3.
      I should see a log entry going at least to 192.168.0.2

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      • KOMK
        KOM
        last edited by KOM

        That means that the client was trying to open a connection (SYN) to pfSense LAN, for whatever reason. That doesn't show it using pfSense to talk to the other client.

        Look, this is basic networking. You asked for help. Why are you now arguing?

        What are these clients? Windows? Linux? Mac?...

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        • KOMK
          KOM
          last edited by

          @HansSolo said in Having LAN issues related to a new switch:

          So let's say I try to connect to 192.168.0.2 from 192.168.0.3.
          I should see a log entry going at least to 192.168.0.2

          No, you should not. Or at least not unless you've got a port-forward in place that NATs some external IP back into your LAN to the other client.

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          • H
            HansSolo @KOM
            last edited by HansSolo

            @KOM

            arguing?
            My my. Am I coming across that way? Sry. Your help is appreciated.

            I guess what's going on here is that the WG Fireboxes I came from ALWAYS logged this traffic.
            I'm used to seeing it.
            I guess it's just something else I have to adjust to.
            Annnnnd maybe I just realized why it might have......hmmmm

            Buit you're right....how can it log traffic that isn't going through it?

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            • KOMK
              KOM
              last edited by

              All I am saying is believe me when I tell you that inter-LAN comms go direct without hitting pfSense. Trust me. NOw about those clients?

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              • H
                HansSolo @KOM
                last edited by

                @KOM

                Windows

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                • KOMK
                  KOM
                  last edited by

                  Windows firewall will automatically block traffic from a different subnet, but it should allow local traffic. As a test, disable the firewall on both clients and try your ping test again.

                  Perhaps your Wireguard was running its LAN interface in promiscuous mode and sucking up every packet it saw hitting its buffer.

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                  • M
                    marvosa @HansSolo
                    last edited by marvosa

                    @HansSolo said in Having LAN issues related to a new switch:

                    So let's say I try to connect to 192.168.0.2 from 192.168.0.3.
                    I should see a log entry going at least to 192.168.0.2

                    Incorrect. Traffic will not hit the firewall unless the destination is outside of 192.168.0.0/24. If both PC's are in the same subnet, you can disconnect PFsense altogether and the two devices will still communicate because the switch is flooding the frame to all ports in the same broadcast domain and will forward the frame to the correct port one it learns the MAC address from the destination PC.

                    If you're having communication issues between two devices in the same subnet, you either have a windows firewall issue or a configuration issue within the software/protocol that you're trying to communicate with.

                    When you say you cannot communicate between PC's... what exactly are you trying to do?

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                    • H
                      HansSolo @KOM
                      last edited by

                      @KOM

                      Never. I ALWAYS disabled Promiscuous mode.

                      But now I'm gonna go back and connect these two to that Firebox just to see.
                      I'm not sure HOW it logged that traffic. But it did.

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                      • KOMK
                        KOM
                        last edited by KOM

                        Either the traffic was between different subnets, or the NIC was in promiscuous mode, or some other device was in promiscuous mode and relaying what it saw to the WG box. It has to be something special because tcp/ip works the same way everywhere. Local IPv4 clients find each other via ARP and talk direct.

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                        • H
                          HansSolo @marvosa
                          last edited by HansSolo

                          @marvosa

                          Hello,

                          Just trying to get two PC's on a local network share.

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                          • KOMK
                            KOM
                            last edited by KOM

                            Can you ping from one to the other? Have you disabled both firewalls and tried to ping?

                            I have to leave for a little bit. BBL.

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                            • johnpozJ
                              johnpoz LAYER 8 Global Moderator
                              last edited by

                              @HansSolo said in Having LAN issues related to a new switch:

                              Just trying to get two PC's on a local network share.

                              As stated already this has ZERO to do with pfsense - ZERO... Other than it being your dhcp server I assume, when it come to device A talking to B that are both on the same network... The router/gateway (pfsense) has ZERO to do with that conversation - zero!!

                              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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                              • chpalmerC
                                chpalmer
                                last edited by

                                IF = Then.

                                If destination address lies within your subnet Then client one goes direct to client two.

                                If destination address lies outside your subnet Then the client traffic is directed at the gateway address. If and only then.

                                Triggering snowflakes one by one..
                                Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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                                • JKnottJ
                                  JKnott @HansSolo
                                  last edited by

                                  @HansSolo said in Having LAN issues related to a new switch:

                                  Not only can I not communicate between these PC's

                                  That has nothing to do with pfSense. Communication between devices on a local LAN do not pass through it.

                                  PfSense running on Qotom mini PC
                                  i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
                                  UniFi AC-Lite access point

                                  I haven't lost my mind. It's around here...somewhere...

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                                  • A
                                    akuma1x
                                    last edited by

                                    @HansSolo
                                    You typed in your original post that all IP addresses are set static. You should go and check all hosts to make sure you typed all the IP addresses in the same subnet and mask. Why don’t you let pfsense DHCP all your network addresses? Then, if you put the hosts on the same physical network, they can all talk to each other, if setup properly.

                                    Jeff

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                                    • H
                                      HansSolo @JKnott
                                      last edited by

                                      @JKnott said in Having LAN issues related to a new switch:

                                      @HansSolo said in Having LAN issues related to a new switch:

                                      Not only can I not communicate between these PC's

                                      That has nothing to do with pfSense. Communication between devices on a local LAN do not pass through it.

                                      right. Like I said, I think I was losing my mind that evening ;-)
                                      thx

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                                      • H
                                        HansSolo @akuma1x
                                        last edited by

                                        @akuma1x said in Having LAN issues related to a new switch:

                                        @HansSolo
                                        You typed in your original post that all IP addresses are set static. You should go and check all hosts to make sure you typed all the IP addresses in the same subnet and mask. Why don’t you let pfsense DHCP all your network addresses? Then, if you put the hosts on the same physical network, they can all talk to each other, if setup properly.

                                        Jeff

                                        Jeff,
                                        Good question.
                                        LONG ago I set up two totally separate networks, OPT1 and OPT2 for various reasons. I never liked DHCP and never really needed it because my network doesn't have various users or devices coming and going. everything is static and I like the control that you hav with static IPs. That and I have some devices that I need to occasionally access remotely and they need to have static IP's.

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                                        • A
                                          akuma1x
                                          last edited by akuma1x

                                          You can still do that with DHCP and static reserved addresses in pfsense, really easy.

                                          Jeff

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                                          • johnpozJ
                                            johnpoz LAYER 8 Global Moderator
                                            last edited by

                                            Dhcp has zero to do with users coming and going..

                                            Most of the time a device will always have the same IP even with dhcp, unless there are more devices than leases and you have device on and off all the time.

                                            Once a device gets a IP via lease - he will continue to renew that IP.. He will even ask for it again when shut off.. The way the dhcpd works is even if that box has been off for really long time - he will still get that IP back because the dhcpd doesn't reuse that lease until he has ran out of other IPs and it has expired, etc..

                                            And you can just always set a reservation for specific device mac address - no that device will always be that IP via dhcp.

                                            The benefit of dhcp is now you can change all your devices to new IP range if so desired without having to actually touch them.. You could change the dns they point to, or the gateway or their domain they use for search suffix, the ntp server they point to, etc. etc.. All without actually having to go touch the physical device.

                                            There is like zero reason not to use dhcp on your network.

                                            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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