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    Not getting DHCP lease from Netgear LB1120 LTE Modem Bridged

    Scheduled Pinned Locked Moved Routing and Multi WAN
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    • chpalmerC
      chpalmer @chpalmer
      last edited by

      Also.. look up the MTU for the carrier you are using.. Verizon is 1400. Wont affect the DHCP but will affect traffic.

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

      M 1 Reply Last reply Reply Quote 0
      • M
        mrn @chpalmer
        last edited by

        @chpalmer

        Here's my pfsense interface:

        interface.png

        Here's my LTE modem configuration (I didn't see any other sections of importance):

        Screenshot from 2025-03-24 23-27-49.png
        Screenshot from 2025-03-24 23-28-09.png

        As you can see from the following image, my laptop got the bridged IP address correctly. Oddly enough, I didn't have to reboot the LTE modem to get this IP.... I wonder if it's permanently tied to my laptop MAC address even through reboots? That doesn't seem right.

        Screenshot from 2025-03-24 23-40-38.png

        M 1 Reply Last reply Reply Quote 0
        • M
          mrn @mrn
          last edited by

          It's not the cable either. I just used the same cable for the router and laptop.

          M 1 Reply Last reply Reply Quote 0
          • M
            michmoor LAYER 8 Rebel Alliance @mrn
            last edited by

            @mrn that’s a weird one. I would look into that system logs to see what’s going on (dhclient) with DHCP.

            Firewall: NetGate,Palo Alto-VM,Juniper SRX
            Routing: Juniper, Arista, Cisco
            Switching: Juniper, Arista, Cisco
            Wireless: Unifi, Aruba IAP
            JNCIP,CCNP Enterprise

            M 1 Reply Last reply Reply Quote 0
            • M
              mrn @michmoor
              last edited by

              @michmoor I already did that in my first post, unless you mean some other place.

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              • M
                michmoor LAYER 8 Rebel Alliance @mrn
                last edited by michmoor

                @mrn yes i see that i apologize.
                This doesnt seem like a pfsense related issue.
                DHCP is 4 message types
                Discover
                Offer
                Request
                Acknowledgement

                pfSense is sending out a broadcast looking for a dhcp server. The dhcp server (cable modem) will hear that broadcast and respond with an offer (public IP from the pool).
                From your system log messages (assuming no filtering of the log messages), pfsense is looking for the dhcp server and its not responding.
                As mentioned it could be a sticky mac address issue where the first record mac learned on the cable modem port is what will get the IP address and subsequent macs get nothing. If so and if rebooting the modem doesnt clear the mac then i would contact the service provider.

                edit: Why are you hard coding a mac address in the pfsense WAN DHCP settings?

                Firewall: NetGate,Palo Alto-VM,Juniper SRX
                Routing: Juniper, Arista, Cisco
                Switching: Juniper, Arista, Cisco
                Wireless: Unifi, Aruba IAP
                JNCIP,CCNP Enterprise

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                • M
                  mrn @michmoor
                  last edited by

                  @michmoor

                  The reason I hardcoded it is that I have an high availability setup. Right now the LTE modem is connected to my secondary pfsense, but I want to me able to move the connection to the primary if necessary. I know that having the same MAC address can make it a seamless transition.

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                  • M
                    mrn @mrn
                    last edited by

                    It won't pull an neither on bridged NOR on router mode.

                    M 1 Reply Last reply Reply Quote 0
                    • M
                      mrn @mrn
                      last edited by

                      @mrn And yes, I have updated it to the latest firmware version.

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                      • M
                        michmoor LAYER 8 Rebel Alliance @mrn
                        last edited by

                        @mrn in Router mode i suspect the cable modem is giving out a DHCP address in the RFC1918 space which based on your screenshot, pfsense will ignore. Uncheck that option and test again.

                        Firewall: NetGate,Palo Alto-VM,Juniper SRX
                        Routing: Juniper, Arista, Cisco
                        Switching: Juniper, Arista, Cisco
                        Wireless: Unifi, Aruba IAP
                        JNCIP,CCNP Enterprise

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                        • M
                          mrn @michmoor
                          last edited by

                          @michmoor Believe it or not, it STILL doesn't pull a DHCP lease.

                          I'm about to return this thing and try something else.

                          chpalmerC 2 Replies Last reply Reply Quote 0
                          • chpalmerC
                            chpalmer @mrn
                            last edited by

                            @mrn uncheck the two boxes for the reserved addresses on your WAN page.

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

                            1 Reply Last reply Reply Quote 0
                            • chpalmerC
                              chpalmer @mrn
                              last edited by

                              @mrn
                              This is how mine is set up.

                              WAN2.png

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

                              M 1 Reply Last reply Reply Quote 0
                              • M
                                mrn @chpalmer
                                last edited by mrn

                                @chpalmer

                                My modem is haunted. Which model do you use?

                                Screenshot from 2025-03-25 18-49-14.png

                                Screenshot from 2025-03-25 18-51-15.png

                                I rebooted the modem, I rebooted pfsense. It just does not work!!

                                M chpalmerC 3 Replies Last reply Reply Quote 0
                                • M
                                  michmoor LAYER 8 Rebel Alliance @mrn
                                  last edited by

                                  @mrn
                                  Desperation.
                                  Try another port other than igb3

                                  Firewall: NetGate,Palo Alto-VM,Juniper SRX
                                  Routing: Juniper, Arista, Cisco
                                  Switching: Juniper, Arista, Cisco
                                  Wireless: Unifi, Aruba IAP
                                  JNCIP,CCNP Enterprise

                                  M 1 Reply Last reply Reply Quote 0
                                  • chpalmerC
                                    chpalmer @mrn
                                    last edited by

                                    @mrn said in Not getting DHCP lease from Netgear LB1120 LTE Modem Bridged:

                                    @chpalmer

                                    My modem is haunted. Which model do you use?

                                    I also use the Netgear LB1120

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

                                    1 Reply Last reply Reply Quote 0
                                    • chpalmerC
                                      chpalmer @mrn
                                      last edited by

                                      @mrn Quit trying to spoof the MAC address.. Not sure why you would need it.

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

                                      1 Reply Last reply Reply Quote 0
                                      • M
                                        mrn @michmoor
                                        last edited by

                                        @michmoor

                                        A different port works!!!

                                        Thank you all!

                                        M 1 Reply Last reply Reply Quote 0
                                        • M
                                          michmoor LAYER 8 Rebel Alliance @mrn
                                          last edited by

                                          @mrn
                                          nice..
                                          dont know whats going on with igb3 in that case but glad its all sorted.

                                          Firewall: NetGate,Palo Alto-VM,Juniper SRX
                                          Routing: Juniper, Arista, Cisco
                                          Switching: Juniper, Arista, Cisco
                                          Wireless: Unifi, Aruba IAP
                                          JNCIP,CCNP Enterprise

                                          M 1 Reply Last reply Reply Quote 0
                                          • M
                                            mrn @michmoor
                                            last edited by

                                            @michmoor

                                            Yeah could be broken in many ways. I haven't used it for anything else. Thankfully I got another spare port.

                                            1 Reply Last reply Reply Quote 1
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