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    Setting up new device on LAN

    Scheduled Pinned Locked Moved General pfSense Questions
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    • P
      peterlecki @johnpoz
      last edited by

      @johnpoz
      Correct, pfSense can see 4.100 but not 4.1
      arp.png.jpg
      It's a dumb switch in between them.

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      • stephenw10S
        stephenw10 Netgate Administrator
        last edited by stephenw10

        You tried swapping the swotch ports the pfSense WAN and laptop are connected to?

        Because some sort of private VLAN setup on the switch could present like this as @johnpoz said.
        Edit: Missed your update

        Steve

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        • stephenw10S
          stephenw10 Netgate Administrator
          last edited by

          Try running a packet capture on WAN in promiscuous mode. You should see at least broadcast traffic from the other hosts in the subnet.

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          • P
            peterlecki @stephenw10
            last edited by peterlecki

            @stephenw10
            Interesting!

            ARP, Request who-has 192.168.4.1 tell 192.168.4.244
            

            So the 4.1 gateway is not responding. Yet it responds to the 4.100 host. Plus the 4.1 device shows 4.244's MAC in its own ARP table. But never responds to the request? I am fucking tripping, man.

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            • stephenw10S
              stephenw10 Netgate Administrator
              last edited by

              Ah, well hallucinogenic substances is one explanation. 😉

              But is it fact responding and the pfSense WAN simply never receives it...

              Try pinging the 4.100 host whilst running a pcap. It should ARP for that too and should see a response.

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              • P
                peterlecki @stephenw10
                last edited by

                @stephenw10
                I do see the ARP request for 4.100 and the reply on the pfSense capture.
                I also ran a promiscuous capture on the 4.100 host and can see ARP requests from 4.244 for 4.1 but 4.1 never responds. I can see it respond to 4.100 but it never responds to 4.244, as if it is completely ignoring any and all packets from that host.

                keyserK 2 Replies Last reply Reply Quote 0
                • keyserK
                  keyser Rebel Alliance @peterlecki
                  last edited by keyser

                  @peterlecki said in Setting up new device on LAN:

                  @stephenw10
                  I do see the ARP request for 4.100 and the reply on the pfSense capture.
                  I also ran a promiscuous capture on the 4.100 host and can see ARP requests from 4.244 for 4.1 but 4.1 never responds. I can see it respond to 4.100 but it never responds to 4.244, as if it is completely ignoring any and all packets from that host.

                  Any chance you have entered a subnetmask on the new pfSense interface by error as /25 or higher?

                  Love the no fuss of using the official appliances :-)

                  stephenw10S 1 Reply Last reply Reply Quote 0
                  • keyserK
                    keyser Rebel Alliance @peterlecki
                    last edited by

                    @peterlecki said in Setting up new device on LAN:

                    @stephenw10
                    I do see the ARP request for 4.100 and the reply on the pfSense capture.
                    I also ran a promiscuous capture on the 4.100 host and can see ARP requests from 4.244 for 4.1 but 4.1 never responds. I can see it respond to 4.100 but it never responds to 4.244, as if it is completely ignoring any and all packets from that host.

                    I just tried placing my SG-2100 behind my primary pfSense, and I am seeing the exact same issue. My downstream pfsense gets a DHCP IP from the primary, but after that any packets sent from the downstream device arrives at the primary, but NO packets are sent as a reply out the LAN interface. Even though states are created, allowed, and nothing is blocked on the primary pfSense.... It's as if it completely ignores that particular device.
                    A force ping towards the downlevel pfSense from the primary is never transmitted from the LAN interface. Any other Ping towards other devices on the same interface works just fine.

                    I'm baffled right now.....

                    Love the no fuss of using the official appliances :-)

                    keyserK 1 Reply Last reply Reply Quote 0
                    • keyserK
                      keyser Rebel Alliance @keyser
                      last edited by keyser

                      @keyser WTF.....

                      When I force ping the downlevel Firewall from the primary, the Ping request goes out the WAN interface - regardless if I auto source it or select the LAN interface as source.

                      For the one particular IP address of the downlevel pfSense (its WAN), my primary pfSense ignores even local connected routing entries and transmits packets toward it on WAN (internet).

                      WTF?

                      EDIT: Looking at the primary's routing table there is a entry for the downlevel pfSenses IP address that uses the WAN gateway. So that entry was somehow created, and I just found out how:

                      This issue arises because there is configured an IPsec tunnel (s2s) between the devices based on DNS names (from ealier on) that obviously can't come up. But the gateway routing line comes from the IPsec S2S definition as that uses the DNS name of the downlevel pfSense (which I updated to a LAN address so I could reach it....)

                      So IPsec S2S was the culprit here.... My mistake.....

                      Love the no fuss of using the official appliances :-)

                      keyserK 1 Reply Last reply Reply Quote 0
                      • keyserK
                        keyser Rebel Alliance @keyser
                        last edited by

                        @keyser Final observation:

                        There seems to be a bug in pfSense as any static routes created out of WAN from a Site2Site gateway definition never expires or gets deleted.
                        To get rid of them requires a reboot.

                        As I change addresses on the downlevel device more and more static routes are added to the primary, and they have no expiration.
                        Neither do they get deleted if I stop the IPsec Service or disable the Site2Site VPN Phase1. Only a full reboot removes the entries.

                        Love the no fuss of using the official appliances :-)

                        luckman212L 1 Reply Last reply Reply Quote 0
                        • stephenw10S
                          stephenw10 Netgate Administrator @keyser
                          last edited by

                          @keyser said in Setting up new device on LAN:

                          Any chance you have entered a subnetmask on the new pfSense interface by error as /25 or higher?

                          If that was the case it would not ARP for 4.100.

                          However a /25 mask on the upstream router might present like this.

                          Try changing the pfSense WAN IP to something inside that like 4.99.

                          Steve

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                          • luckman212L
                            luckman212 LAYER 8 @keyser
                            last edited by

                            @keyser That could be related to the bug I just encountered: https://redmine.pfsense.org/issues/13153

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                            • P
                              peterlecki @stephenw10
                              last edited by

                              @stephenw10
                              I double checked the mask and it was 24. I also changed the IP to 4.99 but it made no difference. From 4.100 I'm able to ping 4.99 and vice versa, ping from 4.99 to 4.100 BUT no comm between 4.1 and 4.99 in either direction. My upstream is a basic SOHO consumer device so I can't see routing tables like @keyser saw in his. I'll try bypassing my upstream device and make pfSense the primary gateway.

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                              • stephenw10S
                                stephenw10 Netgate Administrator
                                last edited by

                                Hmm, bizarre. Some stale ARP cache somewhere? MAC address conflict?

                                johnpozJ 1 Reply Last reply Reply Quote 0
                                • johnpozJ
                                  johnpoz LAYER 8 Global Moderator @stephenw10
                                  last edited by

                                  @stephenw10 what is the arp table look like on the 4.1 device?

                                  If it has a entry for whatever mac pfsense interface IS? or the IP, etc.

                                  An intelligent man is sometimes forced to be drunk to spend time with his fools
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                                  • stephenw10S
                                    stephenw10 Netgate Administrator
                                    last edited by

                                    No way to see it on the ISP router.

                                    johnpozJ 1 Reply Last reply Reply Quote 0
                                    • P
                                      peterlecki @johnpoz
                                      last edited by

                                      @johnpoz @stephenw10
                                      4.1 is not ISP, it's my private device and it has 4.244's correct MAC in its ARP table. All devices had multiple reboots to clear any caches.

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                                      • johnpozJ
                                        johnpoz LAYER 8 Global Moderator @stephenw10
                                        last edited by johnpoz

                                        @stephenw10 said in Setting up new device on LAN:

                                        No way to see it on the ISP router.

                                        You sure he stated

                                        " Plus the 4.1 device shows 4.244's MAC in its own ARP table."

                                        You validated this pfsense actual mac for its wan interface?

                                        Change the interface on pfsense so you get a different mac, or clone the mac to something.. But again there is no way your going to talk to 4.1 if pfsense has no mac.

                                        try setting a static mac for 4.1 on pfsense if your saying 4.1 has the mac address of pfsense.

                                        But you got something crazy going on if your saying pfsense arps for 100 and all work fine, but 4.1 has the mac of pfsense but pfsense doesn't have the mac for 4.1.. You see pfsense send out arp for 4.1 but you do not get an answer?

                                        edit:
                                        Can you post the mac address of both your 4.1 device and pfsense interface your connecting.. There is zero reason to hide the mac.. but if you want you can leave off the last 3... Just curious if a multicast mac.. I had a device one time that was like a bridge for a current cost device that measured power usage for whole house. And it had some oddness - they had used a multicast mac on it... Which can cause some weirdness..

                                        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
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                                        • stephenw10S
                                          stephenw10 Netgate Administrator
                                          last edited by

                                          You can see it here: https://forum.netgate.com/post/1041334
                                          Seems fine.

                                          My mistake on the ISP router. What exactly in the router at 4.1 then?

                                          johnpozJ 1 Reply Last reply Reply Quote 0
                                          • johnpozJ
                                            johnpoz LAYER 8 Global Moderator @stephenw10
                                            last edited by johnpoz

                                            @stephenw10 yeah that mac is not multicast - but what is the mac of this 4.1 device?

                                            This should be simple enough to figure out..

                                            Sniff on both devices - arp from 4.1 for 4.244 or 4.99 whatever pfsense IP is.. Now arp from pfsense for 4.1

                                            Do the other devices see the arp from the other device, do they respond or not.. If they respond is the other device actually seeing it in the sniff?

                                            If device is not reply to the arp, or not sending it out the right interface - then there is something wrong with that device..

                                            But not see a mac for 4.1 in your arp table - you are not going to be able to talk to 4.1 that is for damn sure.. You could see if setting static arp in pfsense for 4.1 allows communication - but that wouldn't be an actual fix, that would be just a work around. Understanding why the normal arp function is not working would be the fix, something is odd for damn sure..

                                            if just a dumb switch.. there really is nothing it could be doing.. It would have an arp cache that is how it knows what mac is on what switch port... But that shouldn't really last that long, have you rebooted the switch? And you have moved pfsense to different port on the switch?

                                            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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